Power saving techniques for sidelink communication

ABSTRACT

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may identify a set of one or more sidelink resources, and the UE may identify wake-up signal occasions associated with the resources. The UE may monitor for wake-up signals during the wake-up signal occasions, and the UE may further monitor the associated set of one or more resources based on receiving a wake-up signal. In some examples, respective sets of one or more sidelink resources may be associated with a number of multiple-input multiple-output layers used for sidelink communications, or may indicate respective bandwidth parts used for monitoring sidelink transmissions.

CROSS REFERENCE

The present application for patent claims the benefit of U.S.Provisional Patent Application No. 62/888,951 by Hosseini et al.,entitled “POWER SAVING TECHNIQUES FOR SIDELINK COMMUNICATION,” filedAug. 19, 2019, assigned to the assignee hereof, and expresslyincorporated by reference in its entirety.

INTRODUCTION

The following relates to wireless communications and more specificallyto techniques enabling power saving at a device.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

SUMMARY

A method of wireless communication at a first UE is described. Themethod may include identifying a set of one or more resources forsidelink communication with a second UE over a sidelink communicationlink and transmitting, to the second UE, a wake-up signal (WUS) over thesidelink communication link. In some examples, the WUS may betransmitted during a WUS occasion that is associated with the set of oneor more resources. The method may also include transmitting, based onthe WUS, a message to the second UE using the set of one or moreresources.

An apparatus for wireless communication is described. The apparatus mayinclude a processor and memory coupled to the processor. The processorand memory may be configured to identify (e.g., at a first UE) a set ofone or more resources for sidelink communication with a second UE over asidelink communication link, and transmit, to the second UE, a WUS overthe sidelink communication link. In some examples, the WUS may betransmitted during a WUS occasion that is associated with the set of oneor more resources. The processor and memory may be configured totransmit, based on the WUS, a message to the second UE using the set ofone or more resources.

Another apparatus for wireless communication is described. The apparatusmay include means for identifying (e.g., at a first UE) a set of one ormore resources for sidelink communication with a second UE over asidelink communication link and transmitting, to the second UE, a WUSover the sidelink communication link. In some examples, the WUS may betransmitted during a WUS occasion that is associated with the set of oneor more resources. In some examples, the apparatus may include means fortransmitting, based on the WUS, a message to the second UE using the setof one or more resources.

A non-transitory computer-readable medium storing code for wirelesscommunication at a first UE is described. The code may includeinstructions executable by a processor to identify a set of one or moreresources for sidelink communication with a second UE over a sidelinkcommunication link, and transmit, to the second UE, a WUS over thesidelink communication link. In some examples, the WUS may betransmitted during a WUS occasion that is associated with the set of oneor more resources. The code may include instructions executable by aprocessor to transmit, based on the WUS, a message to the second UEusing the set of one or more resources.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the set of one ormore resources may include operations, features, means, or instructionsfor receiving, from a base station, a resource grant indicating the setof one or more resources for the sidelink communication, where the WUSassociated with the set of one or more resources may be transmittedbased on the resource grant.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the set of one or moreresources may be associated with a number of multiple input multipleoutput (MIMO) layers.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the set of one ormore resources may include operations, features, means, or instructionsfor selecting the set of one or more resources from a plurality of setsof resources for the sidelink communication, each set of the pluralityof sets of resources being associated with respective WUS occasions,where the WUS associated with the set of one or more resources may betransmitted based on the selected set of one or more resources.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining a number ofMIMO layers for communicating with the second UE over the sidelinkcommunication link, where the set of one or more resources may beselected based on the determined number of MIMO layers.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying one or moregroups of slots for transmitting the message, and transmitting themessage during at least one of the one or more groups of slots, wherethe WUS indicates the one or more groups of slots to the second UE.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more groups ofslots may be indicated to the second UE via a bitmap or a sequence.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the WUS ina first bandwidth part (BWP) of the sidelink communication link, wheretransmitting the message includes transmitting the message in a secondBWP that is different from the first BWP.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the second BWP may be from aset of bandwidth parts (BWPs) associated with the sidelinkcommunication.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the message mayinclude operations, features, means, or instructions for transmittingthe message during one or more sidelink control channel periods, eachsidelink control channel period including a physical sidelink controlchannel and a physical sidelink shared channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each sidelink control channelperiod may have a duration of a slot.

A method of wireless communication at a first UE is described. Themethod may include identifying a set of one or more resources forsidelink communication with a second UE over a sidelink communicationlink and receiving, from the second UE, a WUS over the sidelinkcommunication link. In some examples, the WUS may be received based onmonitoring a WUS occasion that is associated with the set of one or moreresources. The method may further include monitoring the identified setof one or more resources for a transmission from the second UE based onthe received WUS.

An apparatus for wireless communication is described. The apparatus mayinclude a processor and memory coupled to the processor. The processorand memory may be configured to identify (e.g., at a first UE) a set ofone or more resources for sidelink communication with a second UE over asidelink communication link and receive, from the second UE, a WUS overthe sidelink communication link. In some examples, the WUS may bereceived based on monitoring a WUS occasion that is associated with theset of one or more resources. The processor and memory may be configuredto monitor the identified set of one or more resources for atransmission from the second UE based on the received WUS.

Another apparatus for wireless communication at a first UE is described.The apparatus may include means for identifying a set of one or moreresources for sidelink communication with a second UE over a sidelinkcommunication link and receiving, from the second UE, a WUS over thesidelink communication link. In some examples, the WUS may be receivedbased on monitoring a WUS occasion that is associated with the set ofone or more resources. The apparatus may also include means formonitoring the identified set of one or more resources for atransmission from the second UE based on the received WUS.

A non-transitory computer-readable medium storing code for wirelesscommunication at a first UE is described. The code may includeinstructions executable by a processor to identify a set of one or moreresources for sidelink communication with a second UE over a sidelinkcommunication link and receive, from the second UE, a WUS over thesidelink communication link. In some examples, the WUS received based onmonitoring a WUS occasion that is associated with the set of one or moreresources. The instructions executable by a processor to monitor theidentified set of one or more resources for a transmission from thesecond UE based on the received WUS.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the set of one ormore resources may include operations, features, means, or instructionsfor identifying the set of one or more resources based on the receivedWUS.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a bitmapthat indicates the set of one or more resources based on the WUS.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying one or moregroups of slots based on an indication associated with the received WUS,where monitoring the identified set of one or more resources for thetransmission from the second UE may be performed during each of the oneor more groups of slots.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for refraining frommonitoring one or more groups of time periods based on the indication,the one or more groups of time periods including symbol periods, orslots, or a combination thereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the indication includes abitmap associated with the WUS.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the set of one or moreresources may be from a plurality of sets of resources for the sidelinkcommunication, each set of the plurality of sets of resources beingassociated with respective WUS occasions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each set of the plurality ofsets of resources may be associated with a respective number of MIMOlayers.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for monitoring for the WUSin a first BWP of the sidelink communication link, where monitoring theset of one or more resources for the transmission includes monitoring asecond BWP that is different from the first BWP.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the second BWP may be from aset of BWPs associated with the sidelink communication.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, monitoring the set of one ormore resources for the transmission may include operations, features,means, or instructions for monitoring the set of one or more resourcesduring one or more sidelink control channel periods, each sidelinkcontrol channel period including a physical sidelink control channel anda physical sidelink shared channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each sidelink control channelperiod may have a duration of a slot.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the physical sidelink controlchannel and the physical sidelink shared channel may be non-overlappingin time, or non-overlapping in frequency, or overlapping in time, oroverlapping in frequency, or any combination thereof.

A method of wireless communication at a base station is described. Themethod may include identifying a set of one or more resources forsidelink communication between a first UE and second UE over a sidelinkcommunication link, where the set of one or more resources areassociated with one or more WUS occasions. The method may also includetransmitting, to the first UE, a resource grant scheduling the set ofone or more resources on the sidelink communication link.

An apparatus for wireless communication is described. The apparatus mayinclude a processor and memory coupled to the processor. The processorand memory may be configured to identify (e.g., at a base station) a setof one or more resources for sidelink communication between a first UEand second UE over a sidelink communication link, where the set of oneor more resources are associated with one or more WUS occasions. Theprocessor and memory may also be configured to transmit, to the firstUE, a resource grant scheduling the set of one or more resources on thesidelink communication link.

Another apparatus for wireless communication at a base station isdescribed. The apparatus may include means for identifying a set of oneor more resources for sidelink communication between a first UE andsecond UE over a sidelink communication link, where the set of one ormore resources are associated with one or more WUS occasions. Theapparatus may include means for transmitting, to the first UE, aresource grant scheduling the set of one or more resources on thesidelink communication link.

A non-transitory computer-readable medium storing code for wirelesscommunication at a base station is described. The code may includeinstructions executable by a processor to identify a set of one or moreresources for sidelink communication between a first UE and second UEover a sidelink communication link, where the set of one or moreresources are associated with one or more WUS occasions. In someexamples, the instructions may be executable by the processor totransmit, to the first UE, a resource grant scheduling the set of one ormore resources on the sidelink communication link.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the set of one ormore resources may include operations, features, means, or instructionsfor selecting the set of one or more resources from a plurality of setsof resources for the sidelink communication, each set of the pluralityof sets of resources being associated with respective WUS occasions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the set of one ormore resources may include operations, features, means, or instructionsfor determining a number of MIMO layers for the sidelink communication,where the set of one or more resources may be selected based on thedetermined number of MIMO layers.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the set of one or moreresources includes one or more sidelink control channel periods, eachsidelink control channel period including a physical sidelink controlchannel and a physical sidelink shared channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each sidelink control channelperiod may have a duration of a slot.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure.

FIGS. 2A, 2B, and 2C illustrate examples of wireless communicationssystems that support power saving techniques for sidelink communicationin accordance with one or more aspects of the present disclosure.

FIGS. 3A and 3B illustrate an example of a wireless communicationssystem that support power saving techniques for sidelink communicationin accordance with one or more aspects of the present disclosure.

FIG. 4 illustrates an example of a resource allocation timeline thatsupports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure.

FIGS. 5A and 5B illustrate examples of control and data channelconfigurations that support power saving techniques for sidelinkcommunication in accordance with one or more aspects of the presentdisclosure.

FIG. 6 illustrates an example of resource pools that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure.

FIGS. 7A and 7B illustrate examples of wireless communications systemsthat support power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure.

FIGS. 8 and 9 show block diagrams of devices that support power savingtechniques for sidelink communication in accordance with one or moreaspects of the present disclosure.

FIG. 10 shows a block diagram of a UE communications manager thatsupports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure.

FIG. 11 shows a diagram of a system including a device that supportspower saving techniques for sidelink communication in accordance withone or more aspects of the present disclosure.

FIGS. 12 and 13 show block diagrams of devices that support power savingtechniques for sidelink communication in accordance with one or moreaspects of the present disclosure.

FIG. 14 shows a block diagram of a base station communications managerthat supports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure.

FIG. 15 shows a diagram of a system including a device that supportspower saving techniques for sidelink communication in accordance withone or more aspects of the present disclosure.

FIGS. 16 through 19 show flowcharts illustrating methods that supportpower saving techniques for sidelink communication in accordance withone or more aspects of the present disclosure.

DETAILED DESCRIPTION

A wireless communications system may support both access links andsidelinks for communications between wireless devices. An access linkmay refer to a communication link between a user equipment (UE) and abase station. For example, an access link may support uplink signaling,downlink signaling, connection establishment and synchronizationprocedures, etc. A sidelink may refer to communication links betweensimilar wireless devices (e.g., a communication link between UEs or abackhaul communication link between base stations). It is noted thatwhile various examples provided herein are discussed for UE sidelinkdevices, such sidelink techniques may be used for any type of wirelessdevices that use sidelink communications. For example, a sidelink maysupport device-to-device (D2D) communications, vehicle-to-everything(V2X) and/or vehicle-to-vehicle (V2V) communications, message relaying,discovery signaling, beacon signaling, or any combination of these orother signals transmitted over-the-air from one UE to one or more otherUEs.

Sidelink communications may be utilized by UEs in various states ofcoverage within a cell. For example, sidelink communications may includecommunications between two UEs that are both within a coverage areaprovided by a base station, between one UE in coverage and another UEoutside of coverage (e.g., an out-of-coverage UE), or between two UEsthat are both outside of coverage. As these examples illustrate, theremay be cases in which a UE may communicate over a sidelink while outsidethe coverage of a base station, and the UE may therefore lack a directconnection with the network (e.g., via a radio resource control (RRC)link). As a result, an out-of-coverage UE may irregularly monitor forpaging signals from the network and may also be unaware of one or moreother UEs that may be transmitting information to the out-of-coverage UEvia the sidelink communication link. The out-of-coverage UE may thusmonitor sidelink resource pools for sidelink transmissions from otherUEs. Likewise, UEs that are in-coverage may also be unaware of whensidelink transmissions may be sent, and the in-coverage UEs mayaccordingly monitor sidelink resource pools for transmissions fromanother UE. In some cases, such monitoring for sidelink transmission byUEs may be continuous to ensure sidelink transmissions are not missed,and the UEs may consume excess power as a result.

However, as described herein, power saving techniques for sidelinkcommunications may be used to enable reduced power consumption andextended battery life. For example, power savings techniques may beimplemented for a UE through the use of wake-up signals (WUSs) forsidelink communication. In such cases, sets of resources (e.g., resourcepools) may be selected for communications between UEs on a sidelink,where respective resource pools may be associated with different WUSoccasions. For instance, a first set of one or more sidelink resourcepools (e.g., including uplink and downlink resource pools) may beassociated with a first WUS occasion (e.g., having a certain offset froma beginning of one or more physical sidelink control channel (PSCCH)periods), whereas a second set of one or more sidelink resource poolsmay be associated with a second WUS occasion (e.g., having a differentoffset from a beginning of one or more PSCCH periods). In such cases,the WUS occasions may be indicated by the sidelink resource pools usedor, alternatively, a WUS may indicate (e.g., via a bitmap or a WUSsequence) which sidelink resource pools may be used for sidelinkcommunications. In either case, a UE may monitor the sidelink resourcesfor transmissions from another UE on the sidelink based on receiving anassociated WUS. In some examples, the WUS may be UE-specific (e.g., theWUS may be designated to wake up a specific UE, or the WUS may betargeted to wake up a specific group of UEs).

Further, different sets of resource pools may be associated with arespective number of MIMO layers. Thus, sidelink resources may beselected based on a number of MIMO layers appropriate for a sidelinktransmission, providing further granularity for UEs to save powerthrough the use of dynamically selected resources and associated MIMOlayers for sidelink communications. As such, a corresponding WUS may beused to modify the number of MIMO layers by indicating which resourcepools may be monitored by the UE. Additionally or alternatively,different sidelink BWPs may be activated through the use of the sidelinkWUSs, where a WUS may be transmitted on a first BWP that activates asecond, different BWP (e.g., a larger BWP, one or more other BWPsdesignated for sidelink communications, or the like). In some examples,a sidelink WUS may be separate or may depend from a WUS used for adirect link or a Uu link. In such cases where the WUS is independentfrom the Uu link, the sidelink WUS is may change or modify parametersfor sidelink communications, and a different Uu WUS may change or modifythe parameters for Uu communications. In some other cases, if a sidelinkWUS and a Uu WUS are dependent, then a command for one may modify theparameters for the other (e.g., a command associated with a sidelink WUSmay modify parameters for a Uu WUS, or a command for a Uu WUS may modifyparameters for a sidelink WUS). Through one or any combination of thedescribed techniques, UEs may implement various schemes for powersavings enhancements, thereby improving battery life and reducingunnecessary power consumption at the UE when communicating on asidelink.

Aspects of the disclosure are initially described in the context ofwireless communications systems. Further examples of WUSs associatedwith resource pools are then described with reference to wirelesscommunications systems. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to power saving techniquesfor sidelink communication.

FIG. 1 illustrates an example of a wireless communications system 100that supports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure. Thewireless communications system 100 may include base stations 105, UEs115, and a core network 130. In some examples, the wirelesscommunications system 100 may be a Long Term Evolution (LTE) network, anLTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR)network. In some cases, the wireless communications system 100 maysupport enhanced broadband communications, ultra-reliable (e.g., missioncritical) communications, low latency communications, communicationswith low-cost and low-complexity devices, or any combination thereof.

Base stations 105 may be dispersed throughout a geographic area to formthe wireless communications system 100 and may be devices in differentforms or having different capabilities. Base stations 105 and UEs 115may wirelessly communicate via one or more communication links 125. Eachbase station 105 may provide a coverage area 110 over which UEs 115 andthe base station 105 may establish communication links 125. The coveragearea 110 may be an example of a geographic area over which a basestation 105 and a UE 115 support the communication of signals accordingto one or more radio access technologies.

UEs 115 may be dispersed throughout a coverage area 110 of the wirelesscommunications system 100, and each UE 115 may be stationary, or mobile,or both at different times. UEs 115 may be devices in different forms orhaving different capabilities. Some example UEs 115 are illustrated inFIG. 1 . The UEs 115 described herein may be able to communicate withvarious types of devices, such as other UEs 115, base stations 105,and/or network equipment (e.g., core network nodes, relay devices,integrated access and backhaul (IAB) nodes, or other network equipment),as shown in FIG. 1 .

Base stations 105 may communicate with the core network 130, or with oneanother, or both. For example, base stations 105 may interface with thecore network 130 through backhaul links 120 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 120 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105), or indirectly(e.g., via core network 130), or both. In some examples, backhaul links120 may be or include one or more wireless links. One or more of basestations 105 described herein may include or may be referred to by aperson of ordinary skill in the art as a base transceiver station, aradio base station, an access point, a radio transceiver, a NodeB, aneNodeB (eNB), a next-generation NodeB or giga-NodeB (either of which maybe referred to as a gNB), a Home NodeB, a Home eNodeB, or other suitableterminology. In some examples, a UE 115 may communicate with the corenetwork 130 through communication link 135.

A UE 115 may include or may be referred to as a mobile device, awireless device, a remote device, a handheld device, or a subscriberdevice, or some other suitable terminology, where the “device” may alsobe referred to as a unit, a station, a terminal, or a client, amongother examples. A UE 115 may also include or may be referred to as apersonal electronic device such as a cellular phone, a personal digitalassistant (PDA), a tablet computer, a laptop computer, or a personalcomputer. In some examples, a UE 115 may include or be referred to as awireless local loop (WLL) station, an Internet of Things (IoT) device,an Internet of Everything (IoE) device, a machine type communications(MTC) device, or the like, which may be implemented in various objectssuch as appliances, vehicles, meters, or the like.

The UEs 115 described herein may be able to communicate with varioustypes of devices, such as other UEs 115 that may sometimes act as relaysas well as base stations 105 and network equipment including macro eNBsor gNBs, small cell eNBs or gNBs, relay base stations, and the like, asshown in FIG. 1 .

UEs 115 and base stations 105 may wirelessly communicate with oneanother via one or more communication links 125 over one or morecarriers. The term “carrier” may refer to a set of radio frequencyspectrum resources having a defined physical layer structure forsupporting communication links 125. For example, a carrier used for acommunication link 125 may include a portion of a radio frequencyspectrum band (e.g., a BWP) that is operated according to physical layerchannels for a given radio access technology (e.g., LTE, LTE-A, LTE-APro, NR). Each physical layer channel may carry acquisition signaling(e.g., synchronization signals, system information), control signalingthat coordinates operation for the carrier, user data, or othersignaling. The wireless communications system 100 may supportcommunication with a UE 115 using carrier aggregation or multi-carrieroperation. A UE 115 may be configured with multiple downlink componentcarriers and one or more uplink component carriers according to acarrier aggregation configuration. Carrier aggregation may be used withboth frequency division duplexing (FDD) and time division duplexing(TDD) component carriers.

In some examples (e.g., in a carrier aggregation configuration), acarrier may also have acquisition signaling or control signaling thatcoordinates operations for other carriers. A carrier may be associatedwith a frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)) and may be positioned accordingto a channel raster for discovery by UEs 115. A carrier may be operatedin a standalone mode where initial acquisition and connection may beconducted by UEs 115 via the carrier, or the carrier may be operated ina non-standalone mode where a connection is anchored using a differentcarrier (e.g., of the same or a different radio access technology).

Communication links 125 shown in the wireless communications system 100may include uplink transmissions from a UE 115 to a base station 105, ordownlink transmissions from a base station 105 to a UE 115. Carriers maycarry downlink or uplink communications (e.g., in an FDD mode) or may beconfigured to carry downlink and uplink communications (e.g., in a TDDmode).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80megahertz (MHz)). Devices of the wireless communications system 100(e.g., base stations 105, UEs 115, or both) may have hardwareconfigurations that support communications over a particular carrierbandwidth or may be configurable to support communications over one of aset of carrier bandwidths. In some examples, the wireless communicationssystem 100 may include base stations 105 and/or UEs 115 that supportsimultaneous communications via carriers associated with multiplecarrier bandwidths. In some examples, each served UE 115 may beconfigured for operating over portions (e.g., a sub-band, a BWP) or allof a carrier bandwidth.

Signal waveforms transmitted over a carrier may be made up of multiplesubcarriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiplexing (OFDM) or discrete Fouriertransform spread OFDM (DFT-S-OFDM)). In a system employing MCMtechniques, a resource element may consist of one symbol period (e.g., aduration of one modulation symbol) and one subcarrier, where the symbolperiod and subcarrier spacing are inversely related. The number of bitscarried by each resource element may depend on the modulation scheme(e.g., the order of the modulation scheme, the coding rate of themodulation scheme, or both). Thus, the more resource elements that a UE115 receives and the higher the order of the modulation scheme, thehigher the data rate may be for the UE 115. A wireless communicationsresource may refer to a combination of a radio frequency spectrumresource, a time resource, and a spatial resource (e.g., spatial layersor beams), and the use of multiple spatial layers may further increasethe data rate or data integrity for communications with a UE 115.

One or more numerologies for a carrier may be supported, where anumerology may include a subcarrier spacing (Δf) and a cyclic prefix. Acarrier may be divided into BWPs having the same or differentnumerologies. In some examples, a UE 115 may be configured with multipleBWPs. In some cases, a single BWP for a carrier is active at a giventime, and communications for the UE 115 may be restricted to activeBWPs.

Time intervals for base stations 105 or UEs 115 may be expressed inmultiples of a basic time unit which may, for example, refer to asampling period of T_(s)=1/(Δf_(max)·N_(f)) seconds, where Δf_(max) mayrepresent the maximum supported subcarrier spacing, and N_(f) mayrepresent the maximum supported discrete Fourier transform (DFT) size.Time intervals of a communications resource may be organized accordingto radio frames each having a specified duration (e.g., 10 milliseconds(ms)). Each radio frame may be identified by a system frame number (SFN)(e.g., ranging from 0 to 1023).

Each frame may include multiple consecutively numbered subframes orslots, and each subframe or slot may have the same duration. In somecases, a frame may be divided (e.g., in the time domain) into subframes,and each subframe may be further divided into a number of slots.Alternatively, each frame may include a variable number of slots, andthe number of slots may depend on subcarrier spacing. Each slot mayinclude a number of symbol periods (e.g., depending on the length of thecyclic prefix prepended to each symbol period). In some wirelesscommunications systems 100, a slot may further be divided into multiplemini-slots containing one or more symbols. Excluding the cyclic prefix,each symbol period may contain one or more (e.g., N_(f)) samplingperiods. The duration of a symbol period may depend on the subcarrierspacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallestscheduling unit (e.g., in the time domain) of the wirelesscommunications system 100 and may be referred to as a transmission timeinterval (TTI). In some cases, the TTI duration (e.g., the number ofsymbol periods in a TTI) may be variable. Additionally or alternatively,the smallest scheduling unit of the wireless communications system 100may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. A control region (e.g., acontrol resource set (CORESET)) for a physical control channel may bedefined by a number of symbol periods and may extend across the systembandwidth or a subset of the system bandwidth of the carrier. One ormore control regions (e.g., CORESETs) may be configured for a set of UEs115. For example, UEs 115 may monitor or search control regions forcontrol information according to one or more search space sets, and eachsearch space set may include one or multiple control channel candidatesin one or more aggregation levels arranged in a cascaded manner. Anaggregation level for a control channel candidate may refer to a numberof control channel resources (e.g., control channel elements (CCEs))associated with encoded information for a control information formathaving a given payload size. Search space sets may include common searchspace sets configured for sending control information to multiple UEs115 and UE-specific search space sets for sending control information toa specific UE 115.

Each base station 105 may provide communication coverage via one or morecells, for example a macro cell, a small cell, a hot spot, or othertypes of cells, or various combinations thereof. The term “cell” mayrefer to a logical communication entity used for communication with abase station 105 (e.g., over a carrier) and may be associated with anidentifier for distinguishing neighboring cells (e.g., a physical cellidentifier (PCID), a virtual cell identifier (VCID), or others). In someexamples, a cell may also refer to a geographic coverage area 110 or aportion of a geographic coverage area 110 (e.g., a sector) over whichthe logical communication entity operates. Such cells may range fromsmaller areas (e.g., a structure, a subset of structure) to larger areasdepending on various factors such as the capabilities of the basestation 105. For example, a cell may be or include a building, a subsetof a building, exterior spaces between or overlapping with geographiccoverage areas 110, or the like.

A macro cell covers a relatively large geographic area (e.g., severalkilometers in radius) and may allow unrestricted access by UEs 115 withservice subscriptions with the network provider supporting the macrocell. A small cell may be associated with a lower-powered base station105, as compared with a macro cell, and a small cell may operate in thesame or different (e.g., licensed, unlicensed) frequency bands as macrocells. Small cells may provide unrestricted access to UEs 115 withservice subscriptions with the network provider or may providerestricted access to UEs 115 having an association with the small cell(e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 associatedwith users in a home or office, and the like). A base station 105 maysupport one or multiple cells and may also support communications overthe one or more cells using one or multiple component carriers. In someexamples, a carrier may support multiple cells, and different cells maybe configured according to different protocol types (e.g., MTC,narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others)that may provide access for different types of devices.

In some examples, a base station 105 may be movable and thereforeprovide communication coverage for a moving geographic coverage area110. In some examples, different geographic coverage areas 110associated with different technologies may overlap, but the differentgeographic coverage areas 110 may be supported by the same base station105. In other examples, overlapping geographic coverage areas 110associated with different technologies may be supported by differentbase stations 105. The wireless communications system 100 may include,for example, a heterogeneous network in which different types of basestations 105 provide coverage for various geographic coverage areas 110using the same or different radio access technologies.

The wireless communications system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations 105may have similar frame timings, and transmissions from different basestations 105 may be approximately aligned in time. For asynchronousoperation, the base stations 105 may have different frame timings, andtransmissions from different base stations 105 may, in some examples,not be aligned in time. The techniques described herein may be used foreither synchronous or asynchronous operations.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay such information to acentral server or application program that makes use of the informationor presents the information to humans interacting with the applicationprogram. Some UEs 115 may be designed to collect information or enableautomated behavior of machines or other devices. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for UEs 115 include entering a powersaving deep sleep mode when not engaging in active communications,operating over a limited bandwidth (e.g., according to narrowbandcommunications), or a combination of these techniques. For example, someUEs 115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or resource blocks (RBs)) within a carrier, within aguard-band of a carrier, or outside of a carrier.

The wireless communications system 100 may be configured to supportultra-reliable communications or low-latency communications, or variouscombinations thereof. For example, the wireless communications system100 may be configured to support ultra-reliable low-latencycommunications (URLLC) or mission critical communications. UEs 115 maybe designed to support ultra-reliable, low-latency, or criticalfunctions (e.g., mission critical functions). Ultra-reliablecommunications may include private communication or group communicationand may be supported by one or more mission critical services such asmission critical push-to-talk (MCPTT), mission critical video (MCVideo),or mission critical data (MCData). Support for mission criticalfunctions may include prioritization of services, and mission criticalservices may be used for public safety or general commercialapplications. The terms ultra-reliable, low-latency, mission critical,and ultra-reliable low-latency may be used interchangeably herein.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 over a device-to-device (D2D) communication link (e.g.,using a peer-to-peer (P2P) or D2D protocol). One or more UEs 115utilizing D2D communications may be within the geographic coverage area110 of a base station 105. Other UEs 115 in such a group may be outsidethe geographic coverage area 110 of a base station 105 or be otherwiseunable to receive transmissions from a base station 105. In some cases,groups of UEs 115 communicating via D2D communications may utilize aone-to-many (1:M) system in which each UE 115 transmits to every otherUE 115 in the group. In some examples, a base station 105 facilitatesthe scheduling of resources for D2D communications. In other cases, D2Dcommunications are carried out between UEs 115 without the involvementof a base station 105.

In some systems, the D2D communication link (e.g., a sidelinkcommunication link 135) may be an example of a communication channel,such as a sidelink communication channel, between vehicles (e.g., UEs115). In some examples, vehicles may communicate usingvehicle-to-everything (V2X) communications, vehicle-to-vehicle (V2V)communications, or some combination of these. A vehicle may signalinformation related to traffic conditions, signal scheduling, weather,safety, emergencies, or any other information relevant to a V2X system.In some cases, vehicles in a V2X system may communicate with roadsideinfrastructure, such as roadside units, or with the network via one ormore network nodes (e.g., base stations 105) using vehicle-to-network(V2N) communications, or with both.

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC) or 5G core (5GC), which may include at leastone control plane entity that manages access and mobility (e.g., amobility management entity (MME), an access and mobility managementfunction (AMF)) and at least one user plane entity that routes packetsor interconnects to external networks (e.g., a serving gateway (S-GW), aPacket Data Network (PDN) gateway (P-GW), a user plane function (UPF)).The control plane entity may manage non-access stratum (NAS) functionssuch as mobility, authentication, and bearer management for UEs 115served by base stations 105 associated with the core network 130. UserIP packets may be transferred through the user plane entity, which mayprovide IP address allocation as well as other functions. The user planeentity may be connected to the network operators IP services. Theoperators IP services may include access to the Internet, Intranet(s),an IP Multimedia Subsystem (IMS), or a Packet-Switched StreamingService.

Some of the network devices, such as a base station 105, may includesubcomponents such as an access network entity, which may be an exampleof an access node controller (ANC). Each access network entity maycommunicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as radio heads, smartradio heads, or transmission/reception points (TRPs). Each accessnetwork transmission entity may include one or more antenna panels. Insome configurations, various functions of each access network entity orbase station 105 may be distributed across various network devices(e.g., radio heads and ANCs) or consolidated into a single networkdevice (e.g., a base station 105).

The wireless communications system 100 may operate using one or morefrequency bands, for example, in the range of 300 megahertz (MHz) to 300gigahertz (GHz). The region from 300 MHz to 3 GHz is known as theultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features, but the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter ranges (e.g., less than 100 kilometers) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

The electromagnetic spectrum is often subdivided, based onfrequency/wavelength, into various classes, bands, channels, etc. In 5GNR two initial operating bands have been identified as frequency rangedesignations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). Thefrequencies between FR1 and FR2 are often referred to as mid-bandfrequencies. Although a portion of FR1 is greater than 6 GHz, FR1 isoften referred to (interchangeably) as a “Sub-6 GHz” band in variousdocuments and articles. A similar nomenclature issue sometimes occurswith regard to FR2, which is often referred to (interchangeably) as a“millimeter wave” band in documents and articles, despite beingdifferent from the extremely high frequency (EHF) band (30 GHz-300 GHz)which is identified by the International Telecommunications Union (ITU)as a “millimeter wave” band.

With the above aspects in mind, unless specifically stated otherwise, itshould be understood that the term “sub-6 GHz” or the like if usedherein may broadly represent frequencies that may be less than 6 GHz,may be within FR1, or may include mid-band frequencies. Further, unlessspecifically stated otherwise, it should be understood that the term“millimeter wave” or the like if used herein may broadly representfrequencies that may include mid-band frequencies, may be within FR2, ormay be within the EHF band.

The wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band, or in an extremely high frequency (EHF)region of the spectrum (e.g., from 30 GHz to 300 GHz), also known as themillimeter band. In some examples, the wireless communications system100 may support millimeter wave (mmW) communications between UEs 115 andbase stations 105, and EHF antennas of the respective devices may besmaller and more closely spaced than UHF antennas. In some cases, thismay facilitate use of antenna arrays within a device. The propagation ofEHF transmissions, however, may be subject to even greater atmosphericattenuation and shorter range than SHF or UHF transmissions. Techniquesdisclosed herein may be employed across transmissions that use one ormore different frequency regions, and designated use of bands acrossthese frequency regions may differ by country or regulating body.

The wireless communications system 100 may utilize both licensed andunlicensed radio frequency spectrum bands. For example, the wirelesscommunications system 100 may employ License Assisted Access (LAA),LTE-Unlicensed (LTE-U) radio access technology, or NR technology in anunlicensed band such as the 5 GHz industrial, scientific, and medical(ISM) band. When operating in unlicensed radio frequency spectrum bands,devices such as base stations 105 and UEs 115 may employ carrier sensingfor collision detection and avoidance. In some cases, operations inunlicensed bands may be based on a carrier aggregation configuration inconjunction with component carriers operating in a licensed band (e.g.,LAA). Operations in unlicensed spectrum may include downlinktransmissions, uplink transmissions, P2P transmissions, D2Dtransmissions, or the like.

A base station 105 or UE 115 may be equipped with multiple antennas,which may be used to employ techniques such as transmit diversity,receive diversity, MIMO communications, or beamforming. The antennas ofa base station 105 or UE 115 may be located within one or more antennaarrays or antenna panels, which may support MIMO operations or transmitor receive beamforming. For example, one or more base station antennasor antenna arrays may be co-located at an antenna assembly, such as anantenna tower. In some cases, antennas or antenna arrays associated witha base station 105 may be located in diverse geographic locations. Abase station 105 may have an antenna array with a number of rows andcolumns of antenna ports that the base station 105 may use to supportbeamforming of communications with a UE 115. Likewise, a UE 115 may haveone or more antenna arrays that may support various MIMO or beamformingoperations. Additionally or alternatively, an antenna panel may supportradio frequency beamforming for a signal transmitted via an antennaport.

Base stations 105 or UEs 115 may use MIMO communications to exploitmultipath signal propagation and increase the spectral efficiency bytransmitting or receiving multiple signals via different spatial layers.Such techniques may be referred to as spatial multiplexing. The multiplesignals may, for example, be transmitted by the transmitting device viadifferent antennas or different combinations of antennas. Likewise, themultiple signals may be received by the receiving device via differentantennas or different combinations of antennas. Each of the multiplesignals may be referred to as a separate spatial stream and may carrybits associated with the same data stream (e.g., the same codeword) ordifferent data streams (e.g., different codewords). Different spatiallayers may be associated with different antenna ports used for channelmeasurement and reporting. MIMO techniques include single-user MIMO(SU-MIMO), where multiple spatial layers are transmitted to the samereceiving device, and multiple-user MIMO (MU-MIMO), where multiplespatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam, a receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that some signals propagatingat particular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying amplitude offsets, phase offsets, or both to signals carriedvia the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

A base station 105 or UE 115 may use beam sweeping techniques as part ofbeam forming operations. For example, a base station 105 may usemultiple antennas or antenna arrays (e.g., antenna panels) to conductbeamforming operations for directional communications with a UE 115.Some signals (e.g., synchronization signals, reference signals, beamselection signals, or other control signals) may be transmitted by abase station 105 multiple times in different directions. For example,the base station 105 may transmit a signal according to differentbeamforming weight sets associated with different directions oftransmission. Transmissions in different beam directions may be used toidentify (e.g., by a transmitting device, such as a base station 105, ora receiving device, such as a UE 115) a beam direction for subsequenttransmission and/or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based on asignal that was transmitted in different beam directions. For example, aUE 115 may receive one or more of the signals transmitted by the basestation 105 in different directions and may report to the base station105 an indication of the signal that the UE 115 received with a highestsignal quality, or an otherwise acceptable signal quality.

In some cases, transmissions by a device (e.g., by a base station 105 orUE 115) may be performed using multiple beam directions, and the devicemay use a combination of digital precoding or radio frequencybeamforming to generate a combined beam for transmission (e.g., from abase station 105 to a UE 115). The UE 115 may report feedback thatindicates precoding weights for one or more beam directions, and thefeedback may correspond to a configured number of beams across a systembandwidth or one or more sub-bands. The base station 105 may transmit areference signal (e.g., a cell-specific reference signal (CRS), achannel state information reference signal (CSI-RS)), which may beprecoded or unprecoded. The UE 115 may provide feedback for beamselection, which may be a precoding matrix indicator (PMI) orcodebook-based feedback (e.g., a multi-panel type codebook, a linearcombination type codebook, a port selection type codebook). Althoughthese techniques are described with reference to signals transmitted inone or more directions by a base station 105, a UE 115 may employsimilar techniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115) or for transmitting a signal ina single direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115) may try multiple receiveconfigurations (e.g., directional listening) when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets (e.g., differentdirectional listening weight sets) applied to signals received atmultiple antenna elements of an antenna array, or by processing receivedsignals according to different receive beamforming weight sets appliedto signals received at multiple antenna elements of an antenna array,any of which may be referred to as “listening” according to differentreceive configurations or receive directions. In some examples, areceiving device may use a single receive configuration to receive alonga single beam direction (e.g., when receiving a data signal). The singlereceive configuration may be aligned in a beam direction determinedbased on listening according to different receive configurationdirections (e.g., a beam direction determined to have a highest signalstrength, highest signal-to-noise ratio (SNR), or otherwise acceptablesignal quality based on listening according to multiple beamdirections).

The wireless communications system 100 may be a packet-based networkthat operates according to a layered protocol stack. In the user plane,communications at the bearer or Packet Data Convergence Protocol (PDCP)layer may be IP-based. A Radio Link Control (RLC) layer may performpacket segmentation and reassembly to communicate over logical channels.A Medium Access Control (MAC) layer may perform priority handling andmultiplexing of logical channels into transport channels. The MAC layermay also use error detection techniques, error correction techniques, orboth to support retransmissions at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and a base station 105 or corenetwork 130 supporting radio bearers for user plane data. At thePhysical layer, transport channels may be mapped to physical channels.

UEs 115 and base stations 105 may support retransmissions of data toincrease the likelihood that data is received successfully. Hybridautomatic repeat request (HARQ) feedback is one technique for increasingthe likelihood that data is received correctly over a communication link125. HARQ may include a combination of error detection (e.g., using acyclic redundancy check (CRC)), forward error correction (FEC), andretransmission (e.g., automatic repeat request (ARQ)). HARQ may improvethroughput at the MAC layer in poor radio conditions (e.g., lowsignal-to-noise conditions). In some cases, a device may supportsame-slot HARQ feedback, where the device may provide HARQ feedback in aspecific slot for data received in a previous symbol in the slot. Inother cases, the device may provide HARQ feedback in a subsequent slot,or according to some other time interval.

In some cases, a UE 115 may monitor a communication link 125 (e.g., awireless link) 115 continuously for an indication that the UE 115 mayreceive data. In other cases (e.g., to conserve power and extend batterylife) a UE 115 may be configured with a discontinuous reception (DRX)cycle. A DRX cycle consists of an “On Duration” when the UE 115 maymonitor for control information (e.g., on a physical downlink controlchannel (PDCCH)) and a “DRX period” when the UE 115 may power down radiocomponents. In some cases, a UE 115 may be configured with a short DRXcycle and a long DRX cycle. In some cases, a UE 115 may enter a long DRXcycle if it is inactive for one or more short DRX cycles. The transitionbetween the short DRX cycle, the long DRX cycle and continuous receptionmay be controlled by an internal timer or by messaging from a basestation 105. A UE 115 may receive scheduling messages on PDCCH duringthe ON Duration. While monitoring PDCCH for a scheduling message, the UE115 may initiate a “DRX Inactivity Timer”. If a scheduling message issuccessfully received, the UE 115 may prepare to receive data and theDRX Inactivity Timer may be reset. When the DRX Inactivity Timer expireswithout receiving a scheduling message, the UE 115 may move into a shortDRX cycle and may start a “DRX Short Cycle Timer”. When the DRX ShortCycle Timer expires, the UE 115 may resume a long DRX cycle.

Wireless communications system 100 may support various techniques forpower savings when communicating on a sidelink. As an example, a UE 115may determine one or more sidelink DRX parameters for use whencommunicating with another UE 115 over a sidelink communication link.The sidelink DRX parameters may be indicated to the UE 115 by a basestation 105 or by another UE 115 (e.g., an in-coverage UE 115). In someexamples, a UE 115 may select the sidelink DRX parameters from a set ofsidelink DRX parameters, and the UE 115 may indicate the selectedparameters to another UE 115 (e.g., an out-of-coverage UE 115). Based onthe sidelink DRX parameters received, a UE 115 may discontinuouslymonitor for transmissions from another UE 115 over the sidelinkcommunication link. As such, the UE 115 may refrain from continuouslymonitoring for sidelink transmissions in accordance with the sidelinkDRX parameters (e.g., an ON duration, various sidelink DRX timers, andother DRX parameters) and may thereby save power and reduce batteryconsumption at the UE 115.

Wireless communications system 100 may support the use of WUSs for powersaving when communicating on a sidelink communication link 135. As anexample, a UE 115 may identify a set of one or more resources (e.g.,including uplink and downlink time/frequency resources) for sidelinkcommunications. Additionally, the UE 115 may identify WUS occasions thatare associated with the set of one or more resources. In some cases, theset of one or more resources may indicate the WUS occasions to be used.Additionally or alternatively, a WUS may indicate which set of one ormore resources may be used for sidelink communications. In either case,a UE 115 may receive a WUS and monitor associated resources for atransmission from another UE 115 on the sidelink communication link 135.In some cases, the WUS may indicate some time periods (e.g., groupedsymbols and/or slots) during which the sidelink transmission may besent. Thus, when monitoring for the sidelink transmission on thesidelink resource(s), the UE 115 may monitor the indicated time periods,and the UE 115 may, in some examples, refrain from monitoring timeperiods (e.g., other grouped time periods) when the sidelinktransmission is not expected, enabling further power saving at the UE115.

In some cases, the set of one or more sidelink resources may also beassociated with a number of MIMO layers, where different sidelinkresources may each be associated with different numbers of MIMO layers.In some cases, a base station 105 may schedule the set of one or moresidelink resources based on a number of MIMO layers to be used forsidelink transmissions, where the resources scheduled correspond to thenumber of MIMO layers. Additionally or alternatively, a UE 115 mayselect resources associated with an appropriate number of MIMO layersfor sidelink communications. As such, a corresponding WUS may be used tomodify the number of MIMO layers by indicating which resources may bemonitored by a UE 115. In some cases, a BWP including the WUS (e.g., adefault BWP) may be smaller than a size of the BWP used for the set ofone or more sidelink resources. As such, a UE 115 may monitor thedefault BWP for the WUS and, if received, the WUS may activate another,larger BWP for monitoring for a sidelink transmission from another UE115. The other BWP may also be a configured BWP (e.g., one or moresidelink BWPs may be configured), and the WUS may accordingly indicatewhich resources correspond to the activated BWP. Thus, by using varyingBWPs associated with sets of sidelink resources, a BWP may be adjustedto the traffic communicated over the sidelink communication link 135,thereby providing further power saving at the UE 115 (e.g., the UE 115avoids monitoring larger BWPs than needed).

One or more of the base stations 105 may include a base stationcommunications manager 101, which may identify a set of one or moreresources (e.g., resource pools) for sidelink communication between afirst UE 115 and second UE 115 over a sidelink communication link 135,where the set of one or more resources are associated with one or moreWUS occasions and transmit, to the first UE 115, a resource grantscheduling the set of one or more resources on the sidelinkcommunication link 135. The base station communications manager 101 maybe an example of aspects of the base station communications manager 1510described herein.

UEs 115 may include a UE communications manager 102-a, which mayidentify a set of one or more resources (e.g., resource pools) forsidelink communication with a second UE 115 and a second UEcommunications manager 102-b over a sidelink communication link 135,transmit, to the second UE 115, a WUS over the sidelink communicationlink 135, the WUS transmitted during a WUS occasion that is associatedwith the set of one or more resources, and transmit, based on the WUS, amessage to the second UE 115 using the set of one or more resources. TheUE communications manager 102-a may also identify a set of one or moreresources for sidelink communication with a second UE 115 and the UEcommunications manager 102-b over a sidelink communication link 135,receive, from the second UE, a WUS over the sidelink communication link135, the WUS received based on monitoring a WUS occasion that isassociated with the set of one or more resources, and monitor theidentified set of one or more resources for a transmission from thesecond UE 115 based on the received WUS. The UE communications managers102-a and 102-b may be an example of aspects of the UE communicationsmanager 1110 described herein.

FIGS. 2A, 2B, and 2C illustrate examples of wireless communicationssystems 200-a, 200-b, and 200-c that support power saving techniques forsidelink communication in accordance with one or more aspects of thepresent disclosure. In some examples, wireless communications systems200-a, 200-b, and 200-c may implement aspects of wireless communicationssystem 100. For example, wireless communications systems 200-a, 200-b,and 200-c each include a base station 105 (e.g., base station 105-a,base station 105-b, and base station 105-c) and one or more UEs 115(e.g., UEs 115-a through UE 115-f), which may be examples of thecorresponding devices described with reference to FIG. 1 . Wirelesscommunications systems 200-a, 200-b, and 200-c may illustrate variouslevels of coverage for UEs 115 that communicate using sidelinkcommunications.

In some cases, a UE 115-a may communicate directly with another UE 115-b(or with another group of UEs 115) over a sidelink connection (e.g.,using a peer-to-peer (P2P) or device-to-device (D2D) protocol). Suchcommunications may be referred to as D2D or sidelink communications,where a first UE 115 may be scheduled (e.g., by a base station 105 oranother UE 115) to transmit data or control information to a second UE115 over a sidelink. In some cases, a sidelink may be a communicationlink or a signal transmitted between different UEs 115 in a network,where one UE 115 may act as a relay for information transmitted byanother device.

In the example of the wireless communications system 200-a, one or moreof a group of UEs 115 (e.g., UE 115-a and UE 115-b) may support sidelinkcommunications in addition to direct communication with a base station105-a within the coverage area 110 of base station 105-a. In such cases,the UEs 115-a and 115-b may be in-coverage. For example, UE 115-a maycommunicate with the base station 105-a via communication link 225-a,while maintaining sidelink communications over sidelink 230-a with theUE 115-b. In addition, UE 115-b may communicate with the base stationover communication link 225-b while also communicating with UE 115-ausing the sidelink 230-a. In some in-coverage cases, each UE 115 may beconnected to the base station 105 via a direct link (e.g., via a Uuinterface).

In the example of wireless communications system 200-b, one or more of agroup of UEs 115 (e.g., UE 115-c and 115-d) may support sidelinkcommunication techniques. In the example of FIG. 2B, UE 115-c may bewithin the coverage area 110 of the base station 105-b, and UE 115-c maycommunicate directly with the base station 105-b using the communicationlink 225-c. Additionally, UE 115-d may be outside of the coverage area110, and may not communicate using a direct link with the base station105-b (e.g., UE 115-d may not have an established Uu or RRC connectionwith base station 105-b). In other cases, the UE 115-d may be inside thecoverage area 110, but may not be able to communicate directly with thebases station 105-b (e.g., the UE 115-d may experience interference,reduced signal strength, or otherwise impeded communications). In suchcases, the UE 115-d may communicate with the UE 115-c using the sidelink230-b.

In the example of FIG. 2B, the group of UEs 115 may be in partialcoverage (e.g., at least one of the UEs may communicate directly withthe base station, and at least one other UE may be out of coverage). Insuch partial-coverage cases, the UE 115 that is in direct communicationwith the base station (e.g., UE 115-c) may act as a relay forinformation transmitted from the base station 105-b. For example, the UE115-c may receive data or control information directly from the basestation 105-b via communication link 225-c and may relay the informationvia sidelink 230-b to the UE 115-d. In such cases, the UE 115-c mayassist communications between the base station 105-b and the out ofcoverage UE 115-d.

In the example of wireless communications system 200-c, one or more of agroup of UEs 115 (e.g., UE 115-e and 115-f) may communicate outside ofthe coverage area 110 of the base station 105-b using a sidelink. Insome examples, the UE 115-e and the UE 115-f may not have a directconnection to the base station 105-c due to both UEs 115 being outsideof the geographic coverage area 110 of base station 105-c. In some otherexamples, the UEs 115 may be inside the geographic coverage area 110,but may not be able to communicate directly with the base station 105-c(e.g., due to interference, diminished signal strength, etc.). In suchcases, the UEs 115 may be out of coverage and may not have a Uu or otherdirect connection established with the base station 105-c.

UE 115-e may be able to communicate directly with another UE 115-f (orwith another group of UEs 115) over the sidelink 230-c. In suchcommunications, the UEs 115 may communicate without direct connection tothe base station 105-c. However, as illustrated in wirelesscommunications systems 200-a, 200-b, and 200-c, there may be cases inwhich a UE 115 is outside coverage of a base station 105 and may lack adirect, (e.g., RRC) connection with the network while communicating withanother UE 115 via one or more sidelinks 230. Such out-of-coverage UEs115 may not regularly monitor for paging signals from the network, andsome UEs 115 may also be unaware of other UEs 115 that may betransmitting via a sidelink communications link. The out-of-coverage UE115 and in-coverage UE 115 may monitor sidelink resources (e.g.,resource pools) for transmissions from other UEs 115. Such monitoringmay be continuous, and the out-of-coverage UE 115 may unnecessarilyconsume power as a result.

As described herein, techniques may be used in wireless communicationssystems 200-a, 200-b, and 200-c to enable power saving at a devicecommunicating via a sidelink 230. As an example, WUSs for sidelinkcommunications may be transmitted to UEs 115. In such cases, differentsets of sidelink resources may be associated with respective WUSoccasions. As a result, a UE 115 may identify which resources are to bemonitored for sidelink transmissions and may also identify the WUSoccasions corresponding to the resources. As such, the UE 115 mayperiodically awake to monitor for a sidelink WUS, and the UE 115 maymonitor for sidelink communications during the time periods indicated bya received sidelink WUS. Further aspects for power savings include theassociation of different MIMO layers with respective sets of sidelinkresources, as well as using smaller BWPs when monitoring for WUSs andactivating a larger BWP when a received WUS indicates to monitor forsidelink communications. Thus, the described techniques may provide forvarious degrees of power savings for UEs 115 communicating via sidelinks230.

FIGS. 3A and 3B illustrate an example of wireless communications systems300-a and 300-b that support power saving techniques for sidelinkcommunication in accordance with one or more aspects of the presentdisclosure. In some examples, wireless communications systems 300-a and300-b may implement aspects of wireless communications systems 100 and200. For example, wireless communications system 300-a and 300-b eachinclude a base station 105-e and one or more UEs 115 (e.g., UEs 115-iand UE 115-j), which may be examples of the corresponding devicesdescribed with reference to FIGS. 1, 2, and 3 . Wireless communicationssystem 300-a and 300-b may illustrate the signaling of WUSs for powersaving when using sidelink communications.

In some cases, a network may use a WUS in techniques used at a device tofurther increase power savings. The network may implement WUS techniquesfor enhancing DRX communications which may be used by UEs 115-i and115-j. The UEs 115-i and 115-j may be configured to monitor a controlchannel (e.g., a PDCCH, a PSCCH, etc.) according to the ON duration of aconfigured DRX cycle. For example, the UEs 115-i and 115-j may wake upfrom an idle mode during each ON duration of the DRX cycle to monitorfor transmissions on the PDCCH or the PSCCH, and the UEs 115-i and 115-jmay return to an idle or low power mode during each OFF duration of theDRX cycle. In some examples, a WUS sent by a UE 115-i to a UE 115-j on asidelink can be triggered by a UE 115-i itself (e.g., when UE 115-i hasdata to transmit to UE 115-j, UE 115-i may trigger the transmission ofthe WUS). In some other examples, the transmission of the WUS may betriggered by the network (e.g., the base station 105-e directly or bythe base station 105-e to a target UE through a relay device).

To enhance power saving at the UEs 115-i and 115-j, a number of WUSoccasions may be configured in addition to the DRX configuration. EachWUS occasion may in some cases be a low-power signal that may betransmitted before each associated ON occasion of the DRX cycle. In someexamples, the WUS may indicate to the UE 115 which ON occasions it mayskip (e.g., which ON occasions of the DRX cycle that the UE 115 mayremain in a low power state). Additionally or alternatively, the WUS mayindicate to the UE 115 that it may expect to receive data in a followingON duration, such that the UE 115 may awake from low power mode. In someexamples, the WUS may indicate to a UE 115 (e.g., independent of a DRXcycle) that the UE 115 is to wake up and stay up indefinitely, or thatthe UE 115 is to wake up and stay up for a specified duration of time(e.g., a duration of time specified by the WUS).

In some cases, such as in wireless communications system 300-a, the basestation 105-e may receive an indication that the UE 115-i maycommunicate via sidelink communications with an out of coverage UE(e.g., UE 115-j). In such cases, the base station 105-e may transmit asidelink grant 305 to the UE 115-i. The sidelink grant 305 may includeinformation that the UE 115-i may use to communicate with the UE 115-j,for example, sidelink grant 305 may indicate a number of sidelinkresources that the UE 115-i may use to communicate with the UE 115-j. Inaddition, the sidelink grant 305 may include a sidelink DRXconfiguration that the UE 115-i may transmit to the 115-j via theindicated sidelink resources. In some examples, the sidelink DRXconfiguration transmitted to the UE 115-i may include indication of WUSoccasions associated with the indicated sidelink DRX configuration.

In some cases, after communicating with the base station 105-e, the UE115-i may establish a sidelink with the UE 115-j using the sidelinkresources that the base station 105-e indicates to the UE 115-i in thesidelink grant 305 described with reference to FIG. 3A. The UE 115-i mayrelay information it may receive from the base station 105-e to the UE115-j, which may include sidelink DRX configuration information 310 andassociated WUS configurations. In some other cases, the UE 115-i mayselect sidelink resources and a sidelink DRX configuration withoutdirect communication with the base station 105-e.

The information 310 that is sent from UE 115-i to UE 115-j may, in somecases, include a DRX configuration for the UE 115-j. The DRX cycle mayindicate time periods in which UE 115-j may monitor a control channel(e.g., a PDCCH, a PSCCH, etc.) according to the ON duration 320 of aconfigured DRX cycle. For example, the UE 115-j may wake up from an idlemode during each ON duration 320 of the DRX cycle to monitor fortransmissions on the PDCCH or the PSCCH, and the UE 115-j may return toan idle or low power mode during each OFF duration of the DRXconfiguration. A DRX cycle duration 325 may be the time it may take tocomplete an ON duration and an OFF duration of the DRX configuration.

Before the start of each ON duration 320 of the sidelink DRXconfiguration, within a given offset, there may be a WUS occasion 315 tomonitor for the PSCCH WUS. The UE 115-j may wake up to monitor for thePSCCH WUS during each WUS occasion 315 a-c, and if it receives the WUS,it may wake up for the associated ON duration. If the UE 115-j does notreceive the PSCCH WUS during a WUS occasion 315, then it may remain in asleep mode during the next ON duration. In some cases, and as describedin further detail below, various sets of resources (e.g., resourcepools) may be associated with WUS occasions used by the UE 115-j to wakeup and monitor for PSCCH transmissions during a PSCCH period.

FIG. 4 illustrates an example of a resource allocation timeline 400 thatsupports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure. In someexamples, resource allocation timeline 600 may implement aspects ofwireless communications systems 100, 200, and 300.

In some cases, a single target UE 115 or group of target UEs 115 mayreceive data via a sidelink connection from one source UE 115. There maybe a different source UE 115, however, that may attempt to connect withthe multiple target UEs. In such cases (e.g., where the transmission isnot unicast), WUS PDCCH may be implemented to manage or synchronize theDRX. WUS PDCCH or PSCCH signaling may also be implemented in such casesto enable increased power saving at the UEs 115. It is noted that atarget UE 115 and a source UE 115 may correspond to an out-of-coverageUE 115 and an in-coverage UE 115, or vice versa. In other cases, boththe target UE 115 and source UE 115 may both be in-coverage, orout-of-coverage, or any combination thereof. In any case, a WUS may betransmitted, over a sidelink communication link, between different UEs115 irrespective of their coverage with a base station 105.

In some examples, a WUS may be implemented before each PSCCH period,where the PSCCH period indicates the period where PSCCH and a physicalsidelink shared channel (PSSCH) may be sent together over a sidelinkbetween UEs 115. In some examples, the WUS may map to a number ofsidelink slots. Before each group of sidelink slots, there may be amonitoring occasion for the WUS that the UE may monitor and based onmonitoring the monitoring occasion for the WUS, the UE 115 may determinewhether it has to wake up during the associated sidelink slots or not.In some cases, the WUS may be implemented prior to a beginning of eachresource pool period (e.g., a period including configured sidelinkresource pools). As such, a PSCCH period may be correspond to orotherwise be referred to as a resource pool period. In some cases, aPSCCH period may contain a number of subframes, slots, and/or symbolperiods (e.g., OFDM symbol periods) allocated for the PSCCH, and anumber of additional subframes are allocated to the PSSCH data pool. Insome cases, the PSCCH period may be associated with multiple PSSCH datapools. In some other implementations, each slot may contain both controland data (e.g., both PSCCH and PSSCH).

For sidelink communications, a WUS occasion 415 and an offset period 420may be included a time period 410 before each PSCCH/PSSCH period. Insome cases, the UE 115 may transmit PSCCH and PSSCH together in a singleslot or during single time period. The transmitting UE 115 may receive asidelink grant 405 from a base station, and the transmitting UE 115 maywait for the next PSCCH period according to a minimum offset time. Thetransmitting UE 115 may transmit a WUS to the receiving UE 115 during aWUS occasion 415. The receiving UE 115 may monitor the WUS occasion 415,which may be placed a certain offset period 420 before the start of thePSCCH period (the offset period 420 may separate the WUS occasion andthe PSCCH period). The WUS may contain a UE ID or group ID such that ifthe target UE 115 detects a WUS with a matching ID, it may monitor thenext PSCCH period or periods. If the target UE 115 does not receive aWUS during the WUS occasion 415, or if the UE ID or group ID does notindicate that the target UE 115 is to monitor the next PSCCH period, thetarget UE 115 may return to an idle mode and may not wake up to monitorthe next PSCCH period. As described herein, a WUS may be transmitted ona sidelink by a UE 115 irrespective of its coverage status with a basestation 105 (e.g., in-coverage, out-of-coverage, etc.). In suchexamples, a UE 115 that has data to transmit to another UE 115 over thesidelink may transmit a WUS to another UE 115, and the WUS (andcorresponding WUS occasion) may point to one or more resource pools. Inother examples, there may be one WUS occasion per resource pool.

In some examples, a UE 115 may relay uplink traffic for one or moreother (e.g., out-of-coverage) UEs 115, which may provide for coverageenhancement in a system. In such cases, WUS transmissions from theout-of-coverage UEs may be distributed. In some cases, there may be aUE-specific WUS occasion per resource pool, or there may be aUE-specific WUS occasion for a group of resource pools.

FIGS. 5A and 5B illustrates an example of control and data channelconfigurations 500-a and 500-b that supports power saving techniques forsidelink communication in accordance with one or more aspects of thepresent disclosure. In some examples, control and data channelconfigurations 500-a and 500-b may implement aspects of wirelesscommunications systems 100, 200, and 300.

The PSCCH period as described, for example, with respect to FIG. 6 , mayinclude both control and data channel aspects. The PSCCH period 515 maybe configured in various ways, and may include a number of sidelinkslots. The configuration structure of 500-a includes the PSCCH period515 (consisting of 40, 80, 160, or 320 ms duration), which may include anumber or period of slots/subframes. The PSCCH 505 may, in some cases,include up to 40 subframes, and the PSCCH 505 may be transmitted at thebeginning of the PSCCH period 515. A PSSCH data pool 510 may be includedin the PSCCH period 515 following the PSCCH 505. The number of subframesthat may be included in the PSCCH period may be derived, for example,based on a bitmap. The bitmap in some cases may be indicated usingdownlink control information (DCI) transmitted from the base station105, or in some other cases, the DCI may be included as part of theresource pool configuration. The PSSCH bitmap may be repeated until theend of the PSCCH period.

Other configurations of the PSCCH period are possible, for example, thecontrol and data aspects of the PSCCH period may be transmitted together(e.g., each PSCCH and PSSCH pool may be sent together in one slot). Theconfigurations 500-b includes a number transmission configurations forthe PSCCH and the PSSCH, for example, within the PSCCH period asdescribed with reference to FIGS. 6-7A. Each combination of the PSCCHand the PSSCH may be located in the same slot (e.g., each PSCCH/PSSCHblock combination may be transmitted in each slot). Additionally oralternatively, each PSCCH/PSSCH combination may span multiple slots(e.g., each PSCCH/PSSCH may be transmitted across multiple slots). Insome examples, the configurations described for the PSCCH and PSSCH maybe sent by a source UE 115 on a sidelink channel.

Configuration 1A shows an example where the PSCCH and the PSSCH may betransmitted using non-overlapping time resources. In configuration 1A,the frequency resources used by both the PSCCH and the PSSCH may be thesame. Configuration 1B shows an example where the frequency resourcesused by both the PSCCH and the PSSCH may be different.

Configuration 2 shows an example where the PSCCH and the PSSCH may betransmitted using non-overlapping frequency resources which may beassociated with time resources used for transmission. For example, thetime resources used for transmitting the PSCCH and the PSSCH may be thesame.

Configuration 3 shows an example where a portion of the PSCCH and theassociated PSSCH may be transmitted using overlapping time resources innon-overlapping frequency resources. An additional portion of theassociated PSSCH and/or an additional portion of the PSCCH may also betransmitted using non-overlapping time resources.

FIG. 6 illustrates an example of resource pool configurations 600 thatsupport power saving techniques for sidelink communication in accordancewith one or more aspects of the present disclosure. In some examples,resource pool configurations 600 may implement aspects of wirelesscommunications systems 100, 200, and 300.

In some cases, a UE 115 may monitor a number of resource pools oncarrier 615. The UE 115 may monitor the resource pools in order todetermine a resource or a set of resources to use to transmitinformation, for example, via a sidelink.

A transmitting UE 115 may determine to use resources associated witheither resource pool 1 or resource pool 2 to transmit to the receivingUE 115. In some cases, each resource pool may be associated with a WUSoccasion 605. In some cases, the WUS occasion 605 may be offset fromeach resource pool by a different time period based on the differentresource pools. For example, WUS occasion 605-a may be offset fromresource pool 1 by an offset 610-a, and WUS occasion 605-b may be offsetfrom resource pool 2 by an offset 610-b. According to some aspects, areceiving UE 115 may monitor the WUS occasions 605-a and 605-bassociated with each resource pool, and the receiving UE 115 maydetermine, based on the monitoring, whether it may stay awake formonitoring the PSSCH and for associated data to be transmitted in thePSSCH period.

In some cases, there may be one WUS occasion per BWP (each WUS may be aPDCCH transmitted through a PDCCH). Within a data payload of the PDCCHWUS, the transmitting UE 115 may include the ID of the resource poolsthat it may use to transmit data. Additionally or alternatively, one WUSPDCCH may indicate (for example, using a bitmap) which one of theresource pools may be monitored by the receiving UE 115.

The BWP containing the WUS PDCCH or WUS sequence may be a default size.The UE 115 may monitor for the WUS PDCCH in the default BWP according tothe default size of the WUS PDCCH, which may in some cases be smallerthan the PSCCH period. However, when the UE is indicated to startmonitoring the PSCCH, the PSCCH/PSSCH BWP may be larger than the WUSoccasion, and the UE 115 may monitor the PSCCH for a longer period oftime.

In another example, a WUS may be used to activate a sidelink BWP (or maybe used to change the size of the sidelink BWP) in cases where multiplesidelink BWPs are configured. In such cases, the resource indication ofthe WUS indicates the resource pools of the activated BWP. The UE 115may then determine which BWP may be used. In such cases, the BWP sizemay be adjusted based on the traffic/data that may be communicated oversidelink communications.

Each WUS may further indicate (for example, using a bitmap), a number ofslots or a group of slots where the PSCCH may be monitored (per resourcepool, or for all the resource pools). The transmitting UE 115 maytransmit in only some of the slots, so the bitmap included in the WUSmay indicate the number of slots or group of slots whether the receivingUE should monitor the PSCCH (e.g., in-between every two WUS occasions).For example, a 10-bit bitmap may indicate 10 occasions to monitor PSCCH.Additionally, if the resource pool transmission is periodic, the bitmapmay include 10 occasions to monitor PSCCH within each period. In suchcases, whichever occasions are not indicated by the bitmap may not bemonitored by the UE 115.

FIGS. 7A and 7B illustrate examples of wireless communications systems700-a and 700-b that support power saving techniques for sidelinkcommunication in accordance with one or more aspects of the presentdisclosure. In some examples, wireless communications systems 700-a and700-b may implement aspects of wireless communications systems 100, 200,and 300. For example, wireless communications system 700-a and 700-beach include a base station 105-f and one or more UEs 115 (e.g., UEs115-k and UE 115-m), which may be examples of the corresponding devicesdescribed with reference to FIGS. 1, 2, and 3 . Wireless communicationssystems 700-a and 700-b may illustrate different resource poolsassociated with different numbers of MIMO layers.

In some examples, different resource pools monitored by a UE 115 may beassociated with different numbers of MIMO layers used for differentkinds of transmissions. For example, a given number of MIMO layers(e.g., 4 layers) may be used to transmit high data rate (HDR)transmissions, and a different number of MIMO layers (e.g., 2 layers)may be used to transmit other types of transmissions. The number oflayers used for receiving data in some cases may be less than the numberof layers used to transmit data, therefore, in some cases a receiving UE115 may turn off some of its functionality when receiving data, whichmay increase power savings.

A UE 115-k may receive, from base station 105-f, an indication ofresources it may use to transmit via a sidelink with UE 115-m. Accordingto a first mode (e.g., Mode 1, where the base station 105-f indicatesthe sidelink resources to the UE 115-k), the base station 105-f may usea buffer status report (BSR) 705 for sidelink transmissions to schedulethe sidelink resources over a resource pool according to a configurednumber of MIMO layers.

In another example, according to a second mode (e.g., Mode 2, where thetransmitting UE 115-k indicates the sidelink resources to UE 115-m), thetransmitting UE 115-k may select a resource pool with a configurednumber of MIMO layers 715. In some cases, when the UE 115-k determineswhich resource pool to use to transmit data, it may also determine thenumber of MIMO layers each resource pool is associated with. The UE115-k may relay the indication 710 of the resource pool and MIMO layerindication to the UE 115-m. For example, if a resource pool isassociated with four MIMO layers, a UE 115 may receive the PSSCHassociated with those four MIMO layers. However, if the UE 115determines that it may transmit information according to only 2 layers,the UE 115 may turn off some of its antennas associated with higherlevel layers and may receive with two layers. The MIMO layers may beassociated with the resource pool configuration, so a transmittingdevice may know the number of layers associated with each resource pool.For example, if a UE 115 receives an indication that a resource pool isconfigured for up to two MIMO layers, it may accordingly adjust itsfunctionality to account for the configuration (e.g., it may turn onantennas needed to detect only two layers). Therefore, the WUS may alsobe used to modify the number of MIMO layers by indicating which resourcepool may be monitored.

FIG. 8 shows a block diagram 800 of a device 805 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The device 805 may be an exampleof aspects of a UE 115 as described herein. The device 805 may include areceiver 810, a UE communications manager 815, and a transmitter 820.The device 805 may also include a processor. Each of these componentsmay be in communication with one another (e.g., via one or more buses).

The receiver 810 may provide a means for receiving information such aspackets, user data, or control information associated with variousinformation channels (e.g., control channels, data channels, andinformation related to power saving techniques for sidelinkcommunication, etc.). Information may be passed on to other componentsof the device 805. The receiver 810 may be an example of aspects of thetransceiver 1120 described with reference to FIG. 11 . The receiver 810may utilize a single antenna or a set of antennas.

The UE communications manager 815 may be configured to provide orsupport a means for identifying a set of one or more resources forsidelink communication with a second UE over a sidelink communicationlink, transmitting, to the second UE, a WUS over the sidelinkcommunication link, the WUS transmitted during a WUS occasion that isassociated with the set of one or more resources, and transmitting,based on the WUS, a message to the second UE using the set of one ormore resources. The UE communications manager 815 may also be configuredto provide or support a means for identifying a set of one or moreresources for sidelink communication with a second UE over a sidelinkcommunication link, receiving, from the second UE, a WUS over thesidelink communication link, the WUS received based on monitoring a WUSoccasion that is associated with the set of one or more resources, andmonitoring the identified set of one or more resources for atransmission from the second UE based on the received WUS. The UEcommunications manager 815 may be an example of aspects of the UEcommunications manager 1110 described herein.

The UE communications manager 815, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. The UE communications manager maybe an example of means for performing various aspects of power savingtechniques for sidelink communication as described herein. Thecommunications manager 815, or its sub-components, may be implemented inhardware (e.g., in communications management circuitry). Thecommunications manager 815, or its sub-components, may be implemented inhardware (e.g., in communications management circuitry). The circuitrymay comprise of processor, digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), a field programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

In another implementation, the UE communications manager 815, or itssub-components may be executed in code (e.g., as communicationsmanagement software or firmware), executed by a processor, or anycombination thereof. If implemented in code executed by the processor,the functions of the UE communications manager 815, or itssub-components may be executed by a general-purpose processor, a DSP,ASIC, an FPGA, or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

In some examples, the communication manager 815 may be configured toperform various operations (e.g., identifying, transmitting, etc.) usingor otherwise in cooperation with the receiver 810, the transmitter 820,or both.

The UE communications manager 815, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, the UEcommunications manager 815, or its sub-components, may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In some examples, the UE communications manager 815, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 820 may provide a means for transmitting signalsgenerated by other components of the device 805. In some examples, thetransmitter 820 may be collocated with a receiver 810 in a transceivermodule. For example, the transmitter 820 may be an example of aspects ofthe transceiver 1120 described with reference to FIG. 11 . Thetransmitter 820 may utilize a single antenna or a set of antennas.

In some examples, UE communications manager 815 may be implemented as anintegrated circuit or chipset for a mobile device modem, and thereceiver 810 and transmitter 820 may be implemented as analog components(e.g., amplifiers, filters, antennas, etc.) coupled with the mobiledevice modem to enable wireless transmission and reception.

The UE communications manager 815 as described herein may be implementedto realize one or more potential advantages. Various implementations mayenable the UE communications manager 815 to effectively receive andprocess WUSs for sidelink and direct link communications between devicesin a wireless network. At least one implementation may enable the UEcommunications manager 815 to effectively use MIMO techniques forresource selection to further power savings for sidelink.

Based on implementing the power saving techniques as described herein,one or more processors of the device 805 (e.g., processor(s) controllingor incorporated with one or more of receiver 810, the UE communicationsmanager 815, and transmitter 820) may reduce the amount of time a deviceis awake and consuming excess power, which may increase power savings.In addition, the processors of the device 805 may be configured toselectively monitor resource pools to reduce excess wake time whilemonitoring for sidelink resources.

FIG. 9 shows a block diagram 900 of a device 905 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The device 905 may be an exampleof aspects of a device 805, or a UE 115 as described herein. The device905 may include a receiver 910, a UE communications manager 915, and atransmitter 940. The device 905 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 910 may provide a means for receiving information such aspackets, user data, or control information associated with variousinformation channels (e.g., control channels, data channels, andinformation related to power saving techniques for sidelinkcommunication, etc.). Information may be passed on to other componentsof the device 905. The receiver 910 may be an example of aspects of thetransceiver 1120 described with reference to FIG. 11 . The receiver 910may utilize a single antenna or a set of antennas.

The UE communications manager 915 may be an example of aspects of the UEcommunications manager 815 as described herein. The UE communicationsmanager 915 may include a resource identification component 920, awake-up signal component 925, a sidelink communication manager 930, anda monitoring component 935. The UE communications manager 915 may be anexample of aspects of the UE communications manager 1110 describedherein.

The resource identification component 920 may provide a means foridentifying a set of one or more resources for sidelink communicationwith a second UE over a sidelink communication link.

The wake-up signal component 925 may provide a means for transmitting,to the second UE, a WUS over the sidelink communication link, the WUStransmitted during a WUS occasion that is associated with the set of oneor more resources.

The sidelink communication manager 930 may provide a means fortransmitting, based on the WUS, a message to the second UE using the setof one or more resources.

The wake-up signal component 925 may provide a means for receiving, fromthe second UE, a WUS over the sidelink communication link, the WUSreceived based on monitoring a WUS occasion that is associated with theset of one or more resources.

The monitoring component 935 may provide a means for monitoring theidentified set of one or more resources for a transmission from thesecond UE based on the received WUS.

The transmitter 940 may provide a means for transmitting signalsgenerated by other components of the device 905. In some examples, thetransmitter 940 may be collocated with a receiver 910 in a transceivermodule. For example, the transmitter 940 may be an example of aspects ofthe transceiver 1120 described with reference to FIG. 11 . Thetransmitter 940 may utilize a single antenna or a set of antennas.

FIG. 10 shows a block diagram 1000 of a UE communications manager 1005that supports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure. The UEcommunications manager 1005 may be an example of aspects of a UEcommunications manager 815, a UE communications manager 915, or a UEcommunications manager 1110 described herein. The UE communicationsmanager 1005 may include a resource identification component 1010, awake-up signal component 1015, a sidelink communication manager 1020, aresource selection component 1025, and a monitoring component 1030. Eachof these modules may communicate, directly or indirectly, with oneanother (e.g., via one or more buses).

The resource identification component 1010 may identify a set of one ormore resources for sidelink communication with a second UE over asidelink communication link. In some examples, the resourceidentification component 1010 may receive, from a base station, aresource grant indicating the set of one or more resources for thesidelink communication, where the WUS associated with the set of one ormore resources is transmitted based on the resource grant.

In some examples, the resource identification component 1010 may providea means for identifying the set of one or more resources based on thereceived WUS. In some examples, the resource identification component1010 may provide a means for identifying a bitmap that indicates the setof one or more resources based on the WUS. In some cases, the set of oneor more resources are associated with a number of MIMO layers.

In some cases, the set of one or more resources are from a plurality ofsets of resources for the sidelink communication, each set of theplurality of sets of resources being associated with respective WUSoccasions. In some cases, each set of the plurality of sets of resourcesis associated with a respective number of MIMO layers.

The wake-up signal component 1015 may provide a means for transmitting,to the second UE, a WUS over the sidelink communication link, the WUStransmitted during a WUS occasion that is associated with the set of oneor more resources. In some examples, the wake-up signal component 1015may provide a means for receiving, from the second UE, a WUS over thesidelink communication link, the WUS received based on monitoring a WUSoccasion that is associated with the set of one or more resources. Insome examples, transmitting the WUS in a first BWP of the sidelinkcommunication link, where transmitting the message includes transmittingthe message in a second BWP that is different from the first BWP. Insome cases, the second BWP is from a set of BWPs associated with thesidelink communication.

The sidelink communication manager 1020 may provide a means fortransmitting, based on the WUS, a message to the second UE using the setof one or more resources. In some examples, the sidelink communicationmanager 1020 may provide a means for identifying one or more groups ofslots for transmitting the message. In some examples, the sidelinkcommunication manager 1020 may provide a means for transmitting themessage during at least one of the one or more groups of slots, wherethe WUS indicates the one or more groups of slots to the second UE.

In some examples, the sidelink communication manager 1020 may provide ameans for transmitting the message during one or more sidelink controlchannel periods, each sidelink control channel period including aphysical sidelink control channel and a physical sidelink sharedchannel. In some cases, the one or more groups of slots are indicated tothe second UE via a bitmap or a sequence. In some cases, each sidelinkcontrol channel period has a duration of a slot.

The monitoring component 1030 may provide a means for monitoring theidentified set of one or more resources for a transmission from thesecond UE based on the received WUS. In some examples, the monitoringcomponent 1030 may provide a means for identifying one or more groups ofslots based on an indication associated with the received WUS, wheremonitoring the identified set of one or more resources for thetransmission from the second UE is performed during each of the one ormore groups of slots.

In some examples, the monitoring component 1030 may provide a means forrefraining from monitoring one or more groups of time periods based onthe indication, the one or more groups of time periods including symbolperiods, or slots, or a combination thereof. In some examples,monitoring for the WUS in a first BWP of the sidelink communicationlink, where monitoring the set of one or more resources for thetransmission includes monitoring a second BWP that is different from thefirst BWP.

In some examples, the monitoring component 1030 may provide a means formonitoring the set of one or more resources during one or more sidelinkcontrol channel periods, each sidelink control channel period includinga physical sidelink control channel and a physical sidelink sharedchannel. In some cases, the indication includes a bitmap associated withthe WUS. In some cases, the second BWP is from a set of BWPs associatedwith the sidelink communication. In some cases, each sidelink controlchannel period has a duration of a slot.

In some cases, the physical sidelink control channel and the physicalsidelink shared channel are non-overlapping in time, or non-overlappingin frequency, or overlapping in time, or overlapping in frequency, orany combination thereof.

The resource selection component 1025 may select the set of one or moreresources from a plurality of sets of resources for the sidelinkcommunication, each set of the plurality of sets of resources beingassociated with respective WUS occasions, where the WUS associated withthe set of one or more resources is transmitted based on the selectedset of one or more resources.

In some examples, the resource selection component 1025 may determine anumber of MIMO layers for communicating with the second UE over thesidelink communication link, where the set of one or more resources areselected based on the determined number of MIMO layers.

FIG. 11 shows a diagram of a system 1100 including a device 1105 thatsupports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure. Thedevice 1105 may be an example of or include the components of device805, device 905, or a UE 115 as described herein. The device 1105 mayinclude components for bi-directional voice and data communicationsincluding components for transmitting and receiving communications,including a UE communications manager 1110, an I/O controller 1115, atransceiver 1120, an antenna 1125, memory 1130, and a processor 1140.These components may be in electronic communication via one or morebuses (e.g., bus 1145).

The UE communications manager 1110 may be configured to provide orsupport a means for identifying a set of one or more resources forsidelink communication with a second UE over a sidelink communicationlink, transmitting, to the second UE, a WUS over the sidelinkcommunication link, the WUS transmitted during a WUS occasion that isassociated with the set of one or more resources, and transmitting,based on the WUS, a message to the second UE using the set of one ormore resources. The UE communications manager 1110 may also beconfigured to provide or support a means for identifying a set of one ormore resources for sidelink communication with a second UE over asidelink communication link, receiving, from the second UE, a WUS overthe sidelink communication link, the WUS received based on monitoring aWUS occasion that is associated with the set of one or more resources,and monitoring the identified set of one or more resources for atransmission from the second UE based on the received WUS.

The I/O controller 1115 may manage input and output signals for thedevice 1105. The I/O controller 1115 may also manage peripherals notintegrated into the device 1105. In some cases, the I/O controller 1115may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1115 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1115may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1115may be implemented as part of a processor. In some cases, a user mayinteract with the device 1105 via the I/O controller 1115 or viahardware components controlled by the I/O controller 1115.

The transceiver 1120 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1120 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1120 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1125.However, in some cases the device may have more than one antenna 1125,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1130 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 1130 may store computer-readable,computer-executable code 1135 including instructions that, whenexecuted, cause the processor to perform various functions describedherein. In some cases, the memory 1130 may contain, among other things,a basic input/output system (BIOS) which may control basic hardware orsoftware operation such as the interaction with peripheral components ordevices.

The processor 1140 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1140 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1140. The processor 1140 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1130) to cause the device 1105 to perform variousfunctions (e.g., functions or tasks supporting power saving techniquesfor sidelink communication).

The code 1135 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1135 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1135 may not be directly executable by theprocessor 1140 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 12 shows a block diagram 1200 of a device 1205 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The device 1205 may be anexample of aspects of a base station 105 as described herein. The device1205 may include a receiver 1210, a base station communications manager1215, and a transmitter 1220. The device 1205 may also include aprocessor. Each of these components may be in communication with oneanother (e.g., via one or more buses).

The receiver 1210 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to power savingtechniques for sidelink communication, etc.). Information may be passedon to other components of the device 1205. The receiver 1210 may be anexample of aspects of the transceiver 1520 described with reference toFIG. 15 . The receiver 1210 may utilize a single antenna or a set ofantennas.

The base station communications manager 1215 may identify a set of oneor more resources for sidelink communication between a first UE andsecond UE over a sidelink communication link, where the set of one ormore resources are associated with one or more WUS occasions andtransmit, to the first UE, a resource grant scheduling the set of one ormore resources on the sidelink communication link. The base stationcommunications manager 1215 may be an example of aspects of the basestation communications manager 1510 described herein.

The base station communications manager 1215 may be an example of meansfor performing various aspects of power saving techniques for sidelinkcommunications as described herein. The communications manager 1215, orits sub-components, may be implemented in hardware (e.g., incommunications management circuitry). The circuitry may comprise ofprocessors, a DSP, an ASIC, an FPGA or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described in thepresent disclosure.

In another implementation, the base station communications manager 1215,or its sub-components, may be implemented in hardware, code (e.g.,communications management software or firmware) executed by a processor,or any combination thereof. If implemented in code executed by aprocessor, the functions of the base station communications manager1215, or its sub-components may be executed by a general-purposeprocessor, a DSP, an ASIC, an FPGA or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described in thepresent disclosure.

In some examples, the base station communications manager 1215 may beconfigured to perform various operations (e.g., identifying,transmitting) using or otherwise in cooperation with the receiver 1210,the transmitter 1220, or both.

The base station communications manager 1215, or its sub-components, maybe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, the basestation communications manager 1215, or its sub-components, may be aseparate and distinct component in accordance with various aspects ofthe present disclosure. In some examples, the base stationcommunications manager 1215, or its sub-components, may be combined withone or more other hardware components, including but not limited to aninput/output (I/O) component, a transceiver, a network server, anothercomputing device, one or more other components described in the presentdisclosure, or a combination thereof in accordance with various aspectsof the present disclosure.

The transmitter 1220 may transmit signals generated by other componentsof the device 1205. In some examples, the transmitter 1220 may becollocated with a receiver 1210 in a transceiver module. For example,the transmitter 1220 may be an example of aspects of the transceiver1520 described with reference to FIG. 15 . The transmitter 1220 mayutilize a single antenna or a set of antennas.

FIG. 13 shows a block diagram 1300 of a device 1305 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The device 1305 may be anexample of aspects of a device 1205, or a base station 105 as describedherein. The device 1305 may include a receiver 1310, a base stationcommunications manager 1315, and a transmitter 1330. The device 1305 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1310 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to power savingtechniques for sidelink communication, etc.). Information may be passedon to other components of the device 1305. The receiver 1310 may be anexample of aspects of the transceiver 1520 described with reference toFIG. 15 . The receiver 1310 may utilize a single antenna or a set ofantennas.

The base station communications manager 1315 may be an example ofaspects of the base station communications manager 1215 as describedherein. The base station communications manager 1315 may include aresource scheduling component 1320 and a grant manager 1325. The basestation communications manager 1315 may be an example of aspects of thebase station communications manager 1510 described herein.

The resource scheduling component 1320 may identify a set of one or moreresources for sidelink communication between a first UE and second UEover a sidelink communication link, where the set of one or moreresources are associated with one or more WUS occasions.

The grant manager 1325 may transmit, to the first UE, a resource grantscheduling the set of one or more resources on the sidelinkcommunication link.

The transmitter 1330 may transmit signals generated by other componentsof the device 1305. In some examples, the transmitter 1330 may becollocated with a receiver 1310 in a transceiver module. For example,the transmitter 1330 may be an example of aspects of the transceiver1520 described with reference to FIG. 15 . The transmitter 1330 mayutilize a single antenna or a set of antennas.

FIG. 14 shows a block diagram 1400 of a base station communicationsmanager 1405 that supports power saving techniques for sidelinkcommunication in accordance with one or more aspects of the presentdisclosure. The base station communications manager 1405 may be anexample of aspects of a base station communications manager 1215, a basestation communications manager 1315, or a base station communicationsmanager 1510 described herein. The base station communications manager1405 may include a resource scheduling component 1410, a grant manager1415, and a MIMO configuration component 1420. Each of these modules maycommunicate, directly or indirectly, with one another (e.g., via one ormore buses).

The resource scheduling component 1410 may identify a set of one or moreresources for sidelink communication between a first UE and second UEover a sidelink communication link, where the set of one or moreresources are associated with one or more WUS occasions.

In some examples, the resource scheduling component 1410 may select theset of one or more resources from a plurality of sets of resources forthe sidelink communication, each set of the plurality of sets ofresources being associated with respective WUS occasions.

In some cases, the set of one or more resources includes one or moresidelink control channel periods, each sidelink control channel periodincluding a physical sidelink control channel and a physical sidelinkshared channel.

In some cases, each sidelink control channel period has a duration of aslot.

The grant manager 1415 may transmit, to the first UE, a resource grantscheduling the set of one or more resources on the sidelinkcommunication link.

The MIMO configuration component 1420 may determine a number of multipleinput multiple output (MIMO) layers for the sidelink communication,where the set of one or more resources are selected based on thedetermined number of MIMO layers.

FIG. 15 shows a diagram of a system 1500 including a device 1505 thatsupports power saving techniques for sidelink communication inaccordance with one or more aspects of the present disclosure. Thedevice 1505 may be an example of or include the components of device1205, device 1305, or a base station 105 as described herein. The device1505 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including a base station communications manager 1510, anetwork communications manager 1515, a transceiver 1520, an antenna1525, memory 1530, a processor 1540, and an inter-station communicationsmanager 1545. These components may be in electronic communication viaone or more buses (e.g., bus 1550).

The base station communications manager 1510 may identify a set of oneor more resources for sidelink communication between a first UE andsecond UE over a sidelink communication link, where the set of one ormore resources are associated with one or more WUS occasions andtransmit, to the first UE, a resource grant scheduling the set of one ormore resources on the sidelink communication link.

The network communications manager 1515 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1515 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1520 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1520 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1520 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1525.However, in some cases the device may have more than one antenna 1525,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1530 may include RAM, ROM, or a combination thereof. Thememory 1530 may store computer-readable code 1535 including instructionsthat, when executed by a processor (e.g., the processor 1540) cause thedevice to perform various functions described herein. In some cases, thememory 1530 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1540 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1540 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1540. The processor 1540 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1530) to cause the device 1505 to perform various functions(e.g., functions or tasks supporting power saving techniques forsidelink communication).

The inter-station communications manager 1545 may manage communicationswith other base station 105, and the inter-station communicationsmanager 1545 may include a controller or scheduler for controllingcommunications with UEs 115 in cooperation with other base stations 105.For example, the inter-station communications manager 1545 maycoordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1545 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 1535 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1535 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1535 may not be directly executable by theprocessor 1540 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 16 shows a flowchart illustrating a method 1600 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The operations of method 1600may be implemented by a UE 115 (e.g., a first UE) or its components asdescribed herein. For example, the operations of method 1600 may beperformed by a UE communications manager as described with reference toFIGS. 8 through 11 . In some examples, a UE may execute a set ofinstructions to control the functional elements of the UE to perform thefunctions described herein. Additionally or alternatively, a UE mayperform aspects of the functions described herein using special-purposehardware.

At 1605, the first UE may identify a set of one or more resources forsidelink communication with a second UE over a sidelink communicationlink. The operations of 1605 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1605may be performed by a resource identification component as describedwith reference to FIGS. 8 through 11 .

At 1610, the first UE may transmit, to the second UE, a WUS over thesidelink communication link, the WUS transmitted during a WUS occasionthat is associated with the set of one or more resources. The operationsof 1610 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1610 may be performed by awake-up signal component as described with reference to FIGS. 8 through11 .

At 1615, the first UE may transmit, based on the WUS, a message to thesecond UE using the set of one or more resources. The operations of 1615may be performed according to the methods described herein. In someexamples, aspects of the operations of 1615 may be performed by asidelink communication manager as described with reference to FIGS. 8through 11 .

FIG. 17 shows a flowchart illustrating a method 1700 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The operations of method 1700may be implemented by a UE 115 (e.g., a first UE) or its components asdescribed herein. For example, the operations of method 1600 may beperformed by a UE communications manager as described with reference toFIGS. 8 through 11 . In some examples, a UE may execute a set ofinstructions to control the functional elements of the UE to perform thefunctions described herein. Additionally or alternatively, a UE mayperform aspects of the functions described herein using special-purposehardware.

At 1705, the first UE may identify a set of one or more resources forsidelink communication with a second UE over a sidelink communicationlink. The operations of 1705 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1705may be performed by a resource identification component as describedwith reference to FIGS. 8 through 11 .

At 1710, the first UE may select the set of one or more resources from aplurality of sets of resources for the sidelink communication, each setof the plurality of sets of resources being associated with respectiveWUS occasions, where a WUS associated with the set of one or moreresources is to be transmitted based at least in part on the selectedset of one or more resources. The operations of 1710 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1710 may be performed by a resource identificationcomponent as described with reference to FIGS. 8 through 11 .

At 1715, the first UE may transmit, to the second UE, the WUS over thesidelink communication link, the WUS transmitted during a WUS occasionthat is associated with the set of one or more resources. The operationsof 1715 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1715 may be performed by awake-up signal component as described with reference to FIGS. 8 through11 .

At 1720, the first UE may transmit, based on the WUS, a message to thesecond UE using the set of one or more resources. The operations of 1720may be performed according to the methods described herein. In someexamples, aspects of the operations of 1720 may be performed by asidelink communication manager as described with reference to FIGS. 8through 11 .

FIG. 18 shows a flowchart illustrating a method 1800 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The operations of method 1800may be implemented by a UE 115 (e.g., a first UE) or its components asdescribed herein. For example, the operations of method 1800 may beperformed by a UE communications manager as described with reference toFIGS. 8 through 11 . In some examples, a UE may execute a set ofinstructions to control the functional elements of the UE to perform thefunctions described herein. Additionally or alternatively, a UE mayperform aspects of the functions described herein using special-purposehardware.

At 1805, the first UE may identify a set of one or more resources forsidelink communication with a second UE over a sidelink communicationlink. The operations of 1805 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1805may be performed by a resource identification component as describedwith reference to FIGS. 8 through 11 .

At 1810, the first UE may receive, from the second UE, a WUS over thesidelink communication link, the WUS received based on monitoring a WUSoccasion that is associated with the set of one or more resources. Theoperations of 1810 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1810 may beperformed by a wake-up signal component as described with reference toFIGS. 8 through 11 .

At 1815, the UE may monitor the identified set of one or more resourcesfor a transmission from the second UE based on the received WUS. Theoperations of 1815 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1815 may beperformed by a monitoring component as described with reference to FIGS.8 through 11 .

FIG. 19 shows a flowchart illustrating a method 1900 that supports powersaving techniques for sidelink communication in accordance with one ormore aspects of the present disclosure. The operations of method 1900may be implemented by a base station 105 or its components as describedherein. For example, the operations of method 1900 may be performed by abase station communications manager as described with reference to FIGS.12 through 15 . In some examples, a base station may execute a set ofinstructions to control the functional elements of the base station toperform the functions described herein. Additionally or alternatively, abase station may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1905, the base station may identify a set of one or more resourcesfor sidelink communication between a first UE and second UE over asidelink communication link, where the set of one or more resources areassociated with one or more WUS occasions. The operations of 1905 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1905 may be performed by a resourcescheduling component as described with reference to FIGS. 12 through 15.

At 1910, the base station may transmit, to the first UE, a resourcegrant scheduling the set of one or more resources on the sidelinkcommunication link. The operations of 1910 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 1910 may be performed by a grant manager as described withreference to FIGS. 12 through 15 .

The following provides an overview of examples of the presentdisclosure.

Example 1

A method for wireless communication at a first UE, comprising:identifying a set of one or more resources for sidelink communicationwith a second UE over a sidelink communication link; transmitting, tothe second UE, a WUS over the sidelink communication link, the WUStransmitted during a WUS occasion that is associated with the set of oneor more resources; and transmitting, based at least in part on the WUS,a message to the second UE using the set of one or more resources.

Example 2

The method of example 1, wherein identifying the set of one or moreresources comprises: receiving, from a base station, a resource grantindicating the set of one or more resources for the sidelinkcommunication, wherein the WUS associated with the set of one or moreresources is transmitted based at least in part on the resource grant.

Example 3

The method of any of examples 1 through 2, wherein the set of one ormore resources are associated with a number of multiple input multipleoutput (MIMO) layers.

Example 4

The method of any of examples 1 through 3, wherein identifying the setof one or more resources comprises: selecting the set of one or moreresources from a plurality of sets of resources for the sidelinkcommunication, each set of the plurality of sets of resources beingassociated with respective WUS occasions, wherein the WUS associatedwith the set of one or more resources is transmitted based at least inpart on the selected set of one or more resources.

Example 5

The method of example 4, further comprising: determining a number ofmultiple input multiple output (MIMO) layers for communicating with thesecond UE over the sidelink communication link, wherein the set of oneor more resources are selected based at least in part on the determinednumber of MIMO layers.

Example 6

The method of any of examples 1 through 5, further comprising:identifying one or more groups of slots for transmitting the message;and transmitting the message during at least one of the one or moregroups of slots, wherein the WUS indicates the one or more groups ofslots to the second UE.

Example 7

The method of example 6 wherein the one or more groups of slots areindicated to the second UE via a bitmap or a sequence.

Example 8

The method of any of examples 1 through 7, further comprising:transmitting the WUS in a first BWP of the sidelink communication link,wherein transmitting the message comprises transmitting the message in asecond BWP that is different from the first BWP.

Example 9

The method of example 8, wherein the second BWP is from a set of BWPsassociated with the sidelink communication.

Example 10

The method of any of examples 1 through 9, wherein transmitting themessage comprises: transmitting the message during one or more sidelinkcontrol channel periods, each sidelink communications period comprisinga physical sidelink control channel and a physical sidelink sharedchannel.

Example 11

The method of example 11, wherein each sidelink control channel periodhas a duration of a slot.

Example 12

A method for wireless communication at a first user equipment (UE),comprising: identifying a set of one or more resources for sidelinkcommunication with a second UE over a sidelink communication link;receiving, from the second UE, a WUS over the sidelink communicationlink, the WUS received based at least in part on monitoring a WUSoccasion that is associated with the set of one or more resources; andmonitoring the identified set of one or more resources for atransmission from the second UE based at least in part on the receivedWUS.

Example 13

The method of example 12, wherein identifying the set of one or moreresources comprises: identifying the set of one or more resources basedat least in part on the received WUS.

Example 14

The method of example 13, further comprising: identifying a bitmap thatindicates the set of one or more resources based at least in part on theWUS.

Example 15

The method of any of examples 12 through 14, further comprising:identifying one or more groups of slots based at least in part on anindication associated with the received WUS, wherein monitoring theidentified set of one or more resources for the transmission from thesecond UE is performed during each of the one or more groups of slots.

Example 16

The method of example 15, further comprising: refraining from monitoringone or more groups of time periods based at least in part on theindication, the one or more groups of time periods comprising symbolperiods, or slots, or a combination thereof.

Example 17

The method of any of examples 15 through 16, wherein the indicationcomprises a bitmap associated with the WUS.

Example 18

The method of any of examples 12 through 17, wherein the set of one ormore resources are from a plurality of sets of resources for thesidelink communication, each set of the plurality of sets of resourcesbeing associated with respective WUS occasions.

Example 19

The method of any of examples 12 through 18, wherein each set of theplurality of sets of resources is associated with a respective number ofmultiple input multiple output (MIMO) layers.

Example 20

The method of any of examples 12 through 19, further comprising:monitoring for the WUS in a first BWP of the sidelink communicationlink, wherein monitoring the set of one or more resources for thetransmission comprises monitoring a second BWP that is different fromthe first BWP.

Example 21

The method of example 21, wherein the second BWP is from a set of BWPsassociated with the sidelink communication.

Example 22

The method of any of examples 12 through 21, wherein monitoring the setof one or more resources for the transmission comprises: monitoring theset of one or more resources during one or more sidelink control channelperiods, each sidelink communications period comprising a physicalsidelink control channel and a physical sidelink shared channel.

Example 23

The method of example 22, wherein each sidelink control channel periodhas a duration of a slot.

Example 24

The method of any of examples 22 through 23, wherein the physicalsidelink control channel and the physical sidelink shared channel arenon-overlapping in time, or non-overlapping in frequency, or overlappingin time, or overlapping in frequency, or any combination thereof.

Example 25

A method for wireless communication at a base station, comprising:identifying a set of one or more resources for sidelink communicationbetween a first user equipment (UE) and second UE over a sidelinkcommunication link, wherein the set of one or more resources areassociated with one or more WUS occasions; and transmitting, to thefirst UE, a resource grant scheduling the set of one or more resourceson the sidelink communication link.

Example 26

The method of example 25, wherein identifying the set of one or moreresources comprises: selecting the set of one or more resources from aplurality of sets of resources for the sidelink communication, each setof the plurality of sets of resources being associated with respectiveWUS occasions.

Example 27

The method of example 26, wherein identifying the set of one or moreresources comprises: determining a number of multiple input multipleoutput (MIMO) layers for the sidelink communication, wherein the set ofone or more resources are selected based at least in part on thedetermined number of MIMO layers.

Example 28

The method of any of examples 25 through 27, wherein the set of one ormore resources comprises one or more sidelink control channel periods,each sidelink communications period comprising a physical sidelinkcontrol channel and a physical sidelink shared channel.

Example 29

The method of example 28, wherein each sidelink control channel periodhas a duration of a slot.

Example 30

An apparatus for wireless communication comprising at least one meansfor performing a method of any one of the examples 1 through 11.

Example 31

An apparatus for wireless communication comprising at least one meansfor performing a method of any one of the examples 12 through 24.

Example 32

An apparatus for wireless communication comprising at least one meansfor performing a method of any one of the examples 25 through 29.

Example 33

An apparatus for wireless communication comprising a processor andmemory coupled to the processor, the processor and memory configured toperform a method of any one of examples 1 through 11.

Example 34

An apparatus for wireless communication comprising a processor andmemory coupled to the processor, the processor and memory configured toperform a method of any one of examples 12 through 24.

Example 35

An apparatus for wireless communication comprising a processor andmemory coupled to the processor, the processor and memory configured toperform a method of any one of examples 25 through 29.

Example 36

A non-transitory computer-readable medium storing code for wirelesscommunication, the code comprising instructions executable by aprocessor to perform a method of any one of examples 1 through 11.

Example 37

A non-transitory computer-readable medium storing code for wirelesscommunication, the code comprising instructions executable by aprocessor to perform a method of any one of examples 12 through 24.

Example 38

A non-transitory computer-readable medium storing code for wirelesscommunication, the code comprising instructions executable by aprocessor to perform a method of any one of examples 25 through 29.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the operations may berearranged or otherwise modified and that other implementations arepossible. Further, aspects from two or more of the methods may becombined.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may bedescribed for purposes of example, and LTE, LTE-A, LTE-A Pro, or NRterminology may be used in much of the description, the techniquesdescribed herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NRnetworks. For example, the described techniques may be applicable tovarious other wireless communications systems such as Ultra MobileBroadband (UMB), Institute of Electrical and Electronics Engineers(IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, aswell as other systems and radio technologies not explicitly mentionedherein.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, a CPU, an FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyprocessor, controller, microcontroller, or state machine. A processormay also be implemented as a combination of computing devices (e.g., acombination of a DSP and a microprocessor, multiple microprocessors, oneor more microprocessors in conjunction with a DSP core, or any othersuch configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein may be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that may beaccessed by a general-purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that may be used to carry or store desired programcode means in the form of instructions or data structures and that maybe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of computer-readable medium. Disk and disc,as used herein, include CD, laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an example operation that is described as “based oncondition A” may be based on both a condition A and a condition Bwithout departing from the scope of the present disclosure. In otherwords, as used herein, the phrase “based on” shall be construed in thesame manner as the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “example” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communication at a firstuser equipment (UE), comprising: transmitting, to a second UE, a wake-upsignal over a sidelink communication link during a wake-up signaloccasion that corresponds to a set of one or more resources for sidelinkcommunication with the second UE, the wake-up signal indicating a set oftransmission time intervals for the second UE to monitor the set of oneor more resources; and transmitting, in accordance with the wake-upsignal, a message to the second UE using the set of one or moreresources that corresponds to the wake-up signal occasion.
 2. The methodof claim 1, further comprising: selecting the set of one or moreresources from a plurality of sets of one or more resources for thesidelink communication, each set of the plurality of sets of resourcesbeing associated with respective wake-up signal occasions, wherein thewake-up signal associated with the set of one or more resources istransmitted based at least in part on the set of one or more resources.3. The method of claim 2, further comprising: determining a quantity ofmultiple input multiple output (MIMO) layers for communicating with thesecond UE over the sidelink communication link, wherein the set of oneor more resources are selected based at least in part on the quantity ofMIMO layers.
 4. The method of claim 1, further comprising: receiving,from a network entity, a resource grant indicating the set of one ormore resources for the sidelink communication, wherein the wake-upsignal associated with the set of one or more resources is transmittedbased at least in part on the resource grant.
 5. The method of claim 4,wherein the set of one or more resources are associated with a quantityof multiple input multiple output (MIMO) layers.
 6. The method of claim1, further comprising: identifying one or more groups of slots fortransmitting the message; and transmitting the message during at leastone of the one or more groups of slots, wherein the wake-up signalindicates the one or more groups of slots to the second UE.
 7. Themethod of claim 6, wherein the one or more groups of slots are indicatedto the second UE via a bitmap.
 8. The method of claim 1, furthercomprising: transmitting the wake-up signal in a first bandwidth part ofthe sidelink communication link, wherein transmitting the messagecomprises: transmitting the message in a second bandwidth part that isdifferent from the first bandwidth part.
 9. The method of claim 8,wherein the second bandwidth part is from a set of bandwidth partsassociated with the sidelink communication.
 10. The method of claim 1,wherein transmitting the message comprises: transmitting the messageduring one or more sidelink control channel periods, each sidelinkcontrol channel period comprising a physical sidelink control channeland a physical sidelink shared channel.
 11. The method of claim 10,wherein each sidelink control channel period has a duration of a slot.12. A method for wireless communication at a first user equipment (UE),comprising: receiving, from a second UE, a wake-up signal over asidelink communication link based at least in part on monitoring awake-up signal occasion that corresponds to a set of one or moreresources for sidelink communication with the second UE, the wake-upsignal indicating a set of transmission time intervals for the second UEto monitor the set of one or more resources; and monitoring the set ofone or more resources that is associated with the wake-up signaloccasion for a transmission from the second UE corresponding to thereceived wake-up signal.
 13. The method of claim 12, further comprising:identifying the set of one or more resources based at least in part onthe received wake-up signal.
 14. The method of claim 13, furthercomprising: identifying a bitmap that indicates the set of one or moreresources based at least in part on the wake-up signal.
 15. The methodof claim 12, further comprising: identifying one or more groups of slotsbased at least in part on the received wake-up signal indicating the setof transmission time intervals, wherein monitoring the set of one ormore resources for the transmission from the second UE is performedduring each of the one or more groups of slots.
 16. The method of claim15, further comprising: refraining from monitoring one or more groups oftime periods based at least in part on the received wake-up signalindicating the set of transmission time intervals, the one or moregroups of time periods comprising symbol periods, or slots, or acombination thereof.
 17. The method of claim 15, wherein the the wake-upsignal comprises a bitmap indicating the set of transmission timeintervals.
 18. The method of claim 12, wherein the set of one or moreresources are from a plurality of resources for the sidelinkcommunication, each set of one or more resources the plurality ofresources being associated with respective wake-up signal occasions. 19.The method of claim 18, wherein each set of one or more resources theplurality of resources is associated with a respective quantity ofmultiple input multiple output (MIMO) layers.
 20. The method of claim12, further comprising: monitoring for the wake-up signal in a firstbandwidth part of the sidelink communication link, wherein monitoringthe set of one or more resources for the transmission comprises:monitoring a second bandwidth part that is different from the firstbandwidth part.
 21. The method of claim 20, wherein the second bandwidthpart is from a set of bandwidth parts associated with the sidelinkcommunication.
 22. The method of claim 12, wherein monitoring the set ofone or more resources for the transmission comprises: monitoring the setof one or more resources during one or more sidelink control channelperiods, each sidelink control channel period comprising a physicalsidelink control channel and a physical sidelink shared channel.
 23. Themethod of claim 22, wherein each sidelink control channel period has aduration of a slot.
 24. The method of claim 22, wherein the physicalsidelink control channel and the physical sidelink shared channel arenon-overlapping in time, or non-overlapping in frequency, or overlappingin time, or overlapping in frequency, or any combination thereof.
 25. Amethod for wireless communication at a network entity, comprising:identifying a set of one or more resources for sidelink communicationbetween a first user equipment (UE) and second UE over a sidelinkcommunication link, wherein the set of one or more resources correspondto one or more wake-up signal occasions, and wherein the one or morewake-up signal occasions comprise a set of transmission time intervalsfor the first UE or the second UE to monitor the set of one or moreresources; and transmitting, to the first UE, a resource grantscheduling the set of one or more resources that corresponds to the oneor more wake-up signal occasions on the sidelink communication link. 26.The method of claim 25, wherein identifying the set of one or moreresources comprises: selecting the set of one or more resources from aplurality of resources for the sidelink communication, each set of oneor more resources of the plurality of resources being associated withrespective wake-up signal occasions.
 27. The method of claim 26, whereinidentifying the set of one or more resources comprises: determining aquantity of multiple input multiple output (MIMO) layers for thesidelink communication, wherein the set of one or more resources areselected based at least in part on the quantity of MIMO layers.
 28. Themethod of claim 25, wherein the set of one or more resources comprisesone or more sidelink control channel periods, each sidelink controlchannel period comprising a physical sidelink control channel and aphysical sidelink shared channel.
 29. The method of claim 28, whereineach sidelink control channel period has a duration of a slot.
 30. Anapparatus for wireless communication at a first user equipment (UE),comprising: a processor; and memory coupled to the processor, theprocessor and memory configured to: transmit, to a second UE, a wake-upsignal over a sidelink communication link during a wake-up signaloccasion that corresponds to a set of one or more resources for sidelinkcommunication with the second UE, the wake-up signal indicating a set oftransmission time intervals for the second UE to monitor the set of oneor more resources; and transmit, in accordance with the wake-up signal,a message to the second UE using the set of one or more resources thatcorresponds to the wake-up signal occasion.